阅读说明：本技术 识别多层制品中健全结合和薄弱结合之间结合边界的方法和系统 (Method and system for identifying bond boundaries between sound bonds and weak bonds in a multi-layer article ) 是由 B·佩顿 A·鲁明斯基 C·E·普罗特 S·D·斯巴科维奇 于 2020-04-17 设计创作，主要内容包括：一种识别多层制品中健全结合和薄弱结合之间结合边界的方法可包括：确定制品表面上的多个位置；对于所述多个位置中的每个位置,获得从所述制品反射的超声波的全波时域波形；以及对于所述多个位置中的每一对相邻位置,基于在该对相邻位置中的第一位置处生成的第一波形的波形特性与在该对相邻位置中的第二位置处生成的第二波形的波形特性的比较,确定所述第一位置与所述第二位置之间是否存在结合边界；以及响应于确定在所述第一位置和所述第二位置之间存在结合边界,基于所述第一位置和所述第二位置确定边界位置,并且记录所述边界位置。(A method of identifying a bond boundary between a healthy bond and a weak bond in a multi-layer article may include: determining a plurality of locations on a surface of an article; for each of the plurality of locations, obtaining a full-wave time-domain waveform of ultrasonic waves reflected from the article; and for each pair of adjacent locations of the plurality of locations, determining whether a bonding boundary exists between a first location of the pair of adjacent locations and a second location of the pair of adjacent locations based on a comparison of waveform characteristics of a first waveform generated at the first location and waveform characteristics of a second waveform generated at the second location; and in response to determining that a binding boundary exists between the first location and the second location, determining a boundary location based on the first location and the second location and recording the boundary location.)

1. A method of identifying a bond boundary between a healthy bond and a weak bond in an article having a first layer and a second layer, the method comprising:

determining a plurality of locations on a surface of the article;

for each of the plurality of locations, obtaining a full-wave time-domain waveform of ultrasonic waves reflected from the article;

for each pair of adjacent locations of the plurality of locations:

determining whether a bonding boundary exists between a first location and a second location of the pair of adjacent locations based on a comparison of waveform characteristics of a first waveform generated at the first location and waveform characteristics of a second waveform generated at the second location; and

in response to determining that a binding boundary exists between the first location and the second location, a boundary location is determined based on one or both of the first location and the second location, and the boundary location is recorded.

2. The method of claim 1, wherein said obtaining a full-wave time-domain waveform comprises:

transmitting ultrasonic waves through the article via a transducer;

receiving reflected ultrasonic waves with the transducer; and

generating the full-wave time-domain waveform based on the reflected ultrasonic waves.

3. The method of claim 1, wherein said obtaining a full-wave time-domain waveform comprises:

waveform data corresponding to the full-wave time-domain waveform is retrieved from a storage medium.

4. The method of claim 1, wherein:

evaluating the waveform characteristic for a predetermined x-axis range of the first and second waveforms; and is

The predetermined x-axis range is based on a velocity of the acoustic wave through the material of the first layer and a thickness of the first layer.

5. The method of claim 1, wherein the determining whether a bonding boundary exists between the first location and the second location comprises:

counting a first number of peaks of the first waveform;

counting a first number of valleys of the first waveform;

counting a second number of peaks of the second waveform;

counting a second number of valleys of the second waveform;

determining that a binding boundary does not exist between the first location and the second location in response to the first number of peaks being equal to the second number of peaks and the first number of troughs being equal to the second number of troughs; and

determining that a binding boundary exists between the first location and the second location in response to the first number of peaks not being equal to the second number of peaks or the first number of troughs not being equal to the second number of troughs.

6. The method of claim 1, wherein the determining whether a bonding boundary exists between the first location and the second location comprises:

counting a first number of peaks of the first waveform;

counting a first number of valleys of the first waveform;

counting a second number of peaks of the second waveform;

counting a second number of valleys of the second waveform;

determining that a binding boundary does not exist between the first location and the second location in response to a first total of the first number of peaks and the first number of troughs being equal to a second total of the second number of peaks and the second number of troughs; and

determining that a bonding boundary exists between the first location and the second location in response to the first total not being equal to the second total.

7. The method of claim 1, wherein the recording the boundary location comprises marking a surface of the article at a location corresponding to the boundary location.

8. The method of claim 1, wherein the recording the boundary location comprises storing coordinates of the boundary location in a storage medium.

9. The method of claim 1, wherein the waveform characteristic of the first waveform is a characteristic of a fast fourier transform of the first waveform and the waveform characteristic of the second waveform is a characteristic of a fast fourier transform of the second waveform.

10. The method of claim 1, wherein:

the article is a clad article;

the first layer comprises a first metal or a first metal alloy; and is

The second layer includes a second metal or a second metal alloy.

11. The method of claim 10, wherein the first layer is solid state welded to the second layer.

12. The method of claim 11, wherein the first layer is explosion welded to the second layer.

13. A system for identifying a bond boundary between a healthy bond and a weak bond in an article having a first layer and a second layer, the system comprising:

a tool head;

an ultrasonic transducer mounted on the tool head in a fixed position relative to the tool head;

a motor system operably coupled to the tool head and configured to move the tool head along a two-dimensional plane parallel to a surface of the article;

a position sensor configured to output a position signal indicative of a position of the tool head;

a controller operatively coupled to the ultrasound transducer, the motor system, and the position sensor, wherein the controller is configured to perform:

controlling the motor system to move the transducer to a plurality of positions along the surface of the article;

for each of the plurality of locations:

identifying coordinates of the location based on the location signal;

controlling the transducer to transmit ultrasonic waves through the article; and is

Generating a full-wave time-domain waveform based on reflected ultrasonic waves received by the transducer;

for each pair of adjacent locations of the plurality of locations:

determining whether a bonding boundary exists between a first location and a second location of the pair of adjacent locations based on a comparison of waveform characteristics of a first waveform generated at the first location and waveform characteristics of a second waveform generated at the second location; and

in response to determining that a binding boundary exists, boundary coordinates are determined based on one or both of the first location and the second location.

14. The system of claim 13, further comprising a storage medium operatively coupled to the controller;

wherein the controller is configured to record the boundary coordinates by storing the boundary coordinates in the storage medium in response to determining that a bonded boundary exists.

15. The system of claim 13, further comprising a marking tool mounted on the tool head and operably coupled to the controller;

wherein the controller is configured to record the boundary coordinates by controlling the marking tool to mark the surface of the article at the boundary coordinates in response to determining that a binding boundary exists.

16. The system of claim 13, wherein:

the controller is configured to evaluate the waveform characteristic for a predetermined x-axis range of the first and second waveforms; and is

The predetermined x-axis range is based on a velocity of the acoustic wave through the material of the first layer and a thickness of the first layer.

17. The system of claim 13, wherein the controller is configured such that the determining whether a bonding boundary exists between the first location and the second location comprises:

counting a first number of peaks of the first waveform;

counting a first number of valleys of the first waveform;

counting a second number of peaks of the second waveform;

counting a second number of valleys of the second waveform;

determining that a binding boundary does not exist between the first location and the second location in response to the first number of peaks being equal to the second number of peaks and the first number of troughs being equal to the second number of troughs; and

determining that a binding boundary exists between the first location and the second location in response to the first number of peaks not being equal to the second number of peaks or the first number of troughs not being equal to the second number of troughs.

18. The system of claim 13, wherein the controller is configured such that the determining whether a bonding boundary exists between the first location and the second location comprises:

counting a first number of peaks of the first waveform;

counting a first number of valleys of the first waveform;

counting a second number of peaks of the second waveform;

counting a second number of valleys of the second waveform;

determining that a binding boundary does not exist between the first location and the second location in response to a first total of the first number of peaks and the first number of troughs being equal to a second total of the second number of peaks and the second number of troughs; and

determining that a bonding boundary exists between the first location and the second location in response to the first total not being equal to the second total.

19. The system of claim 13, wherein the waveform characteristic of the first waveform is a characteristic of a fast fourier transform of the first waveform and the waveform characteristic of the second waveform is a characteristic of a fast fourier transform of the second waveform.

20. A non-transitory computer-readable storage medium comprising computer-executable instructions that, when executed by a computer, cause the computer to:

obtaining a first waveform relating to a first location on a surface of an article comprising a first layer and a second layer, the first waveform generated by transmitting an ultrasonic wave through the article via a transducer and generating a full-wave time-domain waveform based on a reflected ultrasonic wave received at the transducer;

acquiring a second waveform relating to a second location on the surface of the article, the second waveform generated by transmitting ultrasonic waves through the article via a transducer and generating a full-wave time-domain waveform based on reflected ultrasonic waves received at the transducer;

determining whether a bonding boundary exists between a first location and a second location based on a comparison of waveform characteristics of a first waveform generated at the first location in a pair of adjacent locations and waveform characteristics of a second waveform generated at the second location in the pair of adjacent locations; and

in response to determining that a binding boundary exists between the first location and the second location, a boundary location is determined based on one or both of the first location and the second location, and the boundary location is recorded.

Background

Many articles used in industry and commerce may include multiple layers of parts or materials, such as plastic coatings on metal, rubber coatings on metal, epoxy coatings on metal, plastic coatings on glass, or clad metal parts. An important consideration for the quality of a multilayer component or material is the strength of the bond between layers in the multilayer component or material. For example, in the field of clad metal articles such as explosion welded metals, one common criterion is that the welded article should have a shear strength of at least 20 kilopounds per square inch (ksi).

Failure of a bond, i.e., lack of bonding between layers, or weak bonding between layers, can affect the safety or utility of an article made from the multilayer component or material. For example, a weak or defective bond may cause the components to wear out more quickly, resulting in increased maintenance and replacement costs for the user. In addition, weak or defective bonding in a multilayer component or article can lead to catastrophic failure, resulting in mechanical damage or user injury.

Therefore, it is helpful to test the quality of the bonding of the multilayer parts or materials before using them. Non-destructive testing methods such as ultrasonic testing may be used for quality control in the manufacture of multilayer components or materials. By analyzing the waveforms from the ultrasonic test, the boundary between a healthy binding region and a defective binding region can be identified and marked. The defective bonded area can then be repaired, if possible, or cut from the article and discarded.

While conventional non-destructive inspection techniques may be able to identify areas of bonding failure or lack of bonding between layers, conventional techniques may have difficulty identifying areas of weak bonding. Accordingly, it may be desirable to develop methods and systems that can more reliably identify bond boundaries between sound bonds and weak bonds in a multi-layer article.

Disclosure of Invention

An exemplary embodiment of a method of identifying a bond boundary between a healthy bond and a weak bond in an article having a first layer and a second layer may include determining a plurality of locations on a surface of the article. The method may further include, for each of the plurality of locations, obtaining a full-wave time-domain waveform of the ultrasonic waves reflected from the article. The method may further include, for each pair of adjacent locations of the plurality of locations, determining whether a bonding boundary exists between a first location of the pair of adjacent locations and a second location of the pair of adjacent locations based on a comparison of a waveform characteristic of a first waveform generated at the first location and a waveform characteristic of a second waveform generated at the second location. The method may further include, for each pair of adjacent locations of the plurality of locations, in response to determining that a binding boundary exists between the first location and the second location, determining a boundary location based on one or both of the first location and the second location, and recording the boundary location.

An exemplary embodiment of a system for identifying a bond boundary between a healthy bond and a weak bond in an article having a first layer and a second layer may include: a tool head; an ultrasonic transducer mounted on the tool head in a fixed position; a motor system operatively coupled to the tool head and configured to move the tool head along a two-dimensional plane parallel to a surface of an article; a position sensor configured to output a position signal indicative of a position of the tool head; and a controller operatively coupled to the ultrasonic transducer, the motor system, and the position sensor. The controller may be configured to control the motor system to move the transducer to a plurality of positions along the surface of the article. The controller may be further configured to, for each of the plurality of locations, identify coordinates of the location based on the location signal, control the transducer to transmit ultrasonic waves through the article, and generate a full-wave time-domain waveform based on reflected ultrasonic waves received by the transducer. The controller may be further configured to, for each pair of adjacent locations of the plurality of locations, determine whether a bonding boundary exists between a first location of the pair of adjacent locations and a second location of the pair of adjacent locations based on a comparison of a waveform characteristic of a first waveform generated at the first location and a waveform characteristic of a second waveform generated at the second location. The controller may be further configured to, for each pair of adjacent locations of the plurality of locations, determine boundary coordinates based on one or both of the first location and the second location in response to determining that a bonding boundary exists.

An exemplary embodiment of a non-transitory computer-readable storage medium may include computer-executable instructions that, when executed by a computer, cause the computer to acquire a first waveform associated with a first location on a surface of an article including a first layer and a second layer. The first waveform may be generated by transmitting an ultrasonic wave through the article via a transducer and generating a full-wave time-domain waveform based on reflected ultrasonic waves received at the transducer. The computer-executable instructions may also cause the computer to acquire a second waveform associated with a second location on the surface of the article. The second waveform may be generated by transmitting an ultrasonic wave through the article via the transducer and generating a full-wave time-domain waveform based on reflected ultrasonic waves received at the transducer. The computer-executable instructions may further cause the computer to determine whether a bonding boundary exists between a first location of a pair of adjacent locations and a second location of the pair of adjacent locations based on a comparison of waveform characteristics of a first waveform generated at the first location and waveform characteristics of a second waveform generated at the second location; and in response to determining that a binding boundary exists between the first location and the second location, determining a boundary location based on one or both of the first location and the second location and recording the boundary location.

Drawings

A more particular description will be rendered by reference to exemplary embodiments that are illustrated in the appended drawings. Understanding that these drawings depict exemplary embodiments and are not therefore to be considered to be limiting of the disclosure, the exemplary embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1 is a schematic illustration of a multilayer article according to an exemplary embodiment;

FIG. 2 is an exploded schematic view of a multilayer article according to an exemplary embodiment;

FIG. 3 is a flowchart of a method of identifying a bond boundary between a healthy bond and a weak bond in accordance with an exemplary embodiment;

FIG. 4 is a flowchart of a method of identifying a bond boundary between a healthy bond and a weak bond in accordance with an exemplary embodiment;

FIG. 5 is a flowchart of a method of comparing characteristics of waveforms and determining whether a bonded boundary exists between two points, according to an example embodiment;

FIG. 6 is a flowchart of a method of comparing characteristics of waveforms and determining whether a bonded boundary exists between two points, according to an example embodiment;

FIG. 7 is a schematic illustration of a surface of a multilayer article according to an exemplary embodiment;

FIG. 8 is a schematic illustration of an ultrasonic waveform of a multilayer article according to an exemplary embodiment;

FIG. 9 is a schematic illustration of an ultrasonic waveform of a multilayer article according to an exemplary embodiment;

FIG. 10 is a schematic illustration of a surface of a multilayer article according to an exemplary embodiment;

FIG. 11 is a schematic diagram of a system for identifying a bond boundary between a healthy bond and a weak bond in a multi-layer article, according to an example embodiment;

FIG. 12 is a schematic block diagram of a system for identifying a bond boundary between a healthy bond and a weak bond in a multi-layer article in accordance with an exemplary embodiment;

FIG. 13 is a schematic illustration of a surface of a multilayer article according to an exemplary embodiment;

FIG. 14 is a low magnification optical micrograph of a bonding surface of a cladding of a clad article according to an exemplary embodiment;

FIG. 15 is a low magnification optical micrograph of a bonding surface of a base layer of a clad article according to an exemplary embodiment;

FIG. 16 is a low magnification optical micrograph of a bonding surface of a cladding of a clad article according to an exemplary embodiment;

FIG. 17 is a low magnification optical micrograph of a bonding surface of a base layer of a clad article according to an exemplary embodiment;

FIG. 18 is a high magnification optical micrograph of a bonding surface of a cladding of a clad article according to an exemplary embodiment;

FIG. 19 is a high magnification optical micrograph of a bonding surface of a base layer of a clad article according to an exemplary embodiment;

FIG. 20 is a high magnification optical micrograph of a bonding surface of a cladding of a clad article according to an exemplary embodiment;

FIG. 21 is a high magnification optical micrograph of a bonding surface of a base layer of a clad article according to an exemplary embodiment;

FIG. 22 is a scanning electron microscope photomicrograph of the bonding surface of the cladding of the clad article according to an exemplary embodiment;

FIG. 23 is a scanning electron microscope photomicrograph of the bonding surface of the cladding of a clad article according to an exemplary embodiment;

FIG. 24 is a scanning electron microscope photomicrograph of the bonding surface of the cladding of the clad article according to an exemplary embodiment;

FIG. 25 is a scanning electron microscope photomicrograph of the bonding surface of the cladding of the clad article according to an exemplary embodiment;

FIG. 26 is a scanning electron microscope photomicrograph of the bonding surface of the cladding of the clad article according to an exemplary embodiment;

FIG. 27 is a scanning electron microscope photomicrograph of the bonding surface of the cladding of a clad article according to an exemplary embodiment;

FIG. 28 is a scanning electron microscope photomicrograph of the bonding surface of the cladding of the clad article according to an exemplary embodiment;

FIG. 29 is a scanning electron microscope photomicrograph of the bonding surface of the cladding of a clad article according to an exemplary embodiment;

FIG. 30 is a flowchart of a method of comparing characteristics of waveforms and determining whether a bonded boundary exists between two points, according to an exemplary embodiment; and

FIG. 31 is a graph of a fast Fourier transform of an ultrasonic waveform of a comparative clad article according to an exemplary embodiment.

Various features, aspects, and advantages of the exemplary embodiments will become more apparent from the following detailed description and drawings in which like reference numerals represent like parts throughout the drawings and the detailed description. The various features described are not necessarily drawn to scale in the drawings, but are drawn to emphasize specific features relevant to some embodiments.

The headings used herein are for organizational purposes only and are not meant to limit the scope of the disclosure or the claims. To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.

Detailed Description

Reference will now be made in detail to various embodiments. The various examples are provided by way of explanation and are not meant to be limiting and do not constitute a definition of all possible embodiments.

Fig. 1 illustrates an exemplary embodiment of an article 100 having multiple layers. Article 100 may include a base layer 110 and a cladding layer 120 bonded to base layer 110. The article may include an interface 105 between the base layer 110 and the cladding layer 120, and the interface 105 may correspond to a bond between the base layer 110 and the cladding layer 120.

In an exemplary embodiment, the article 100 may be a clad metal article. The base layer 110 may be formed of a material such as stainless steel, carbon steel, titanium, nickel, aluminum, or an alloy including any of these materials. In an exemplary embodiment, the cladding 120 may be formed of a material such as aluminum, steel, titanium, zirconium, copper, silver, tantalum, or an alloy including any of these materials. However, it should be understood that base layer 110 and cladding layer 120 are not limited to these materials, and that other materials may be used depending on the requirements of a particular application. Cladding layer 120 may be bonded to base layer 110 by a solid state welding process, thereby forming interface 105 between cladding layer 120 and first metal layer 110. Interface 105 may be a region between cladding layer 120 and base layer 110 in which atoms from each of cladding layer 120 and base layer 110 diffuse into each other.

Solid state welding may include a set of welding processes that produce a bond/weld between structural elements at a temperature below the melting point of the substrates being joined, without the addition of a brazing filler metal. In exemplary embodiments, solid state welding may be described as a bonding/welding process that (i) does not subject a portion of the structural elements to a liquid or gas phase, (ii) uses pressure, (iii) with or without temperature. Solid state welding is performed over a wide range of pressures and temperatures with significant deformation and solid state diffusion of the substrate. Solid state welding processes include cold welding, diffusion welding, explosive welding, forge welding, friction welding, hot press welding, roll welding, and ultrasonic welding.

In an exemplary embodiment, the solid state weld between the base layer 110 and the cladding layer 120 may be an explosive weld. Explosion welding ("EXW") is a solid state welding technique that uses controlled explosions to force dissimilar metals into a high quality metallurgically bonded joint. The transition joint between dissimilar metals has high mechanical strength, is ultra-high vacuum tight and can withstand severe thermal excursions. EXW is a solid phase process whereby two metals are welded or clad together by using an explosive to accelerate one of the components at an extremely high rate. This process is solid phase because both components are in the solid state of matter at any time.

While article 100 is described above as a solid state welded article, and more particularly as an explosion welded article, it should be understood that the embodiments described herein may also be applied to other types of articles, such as conventional weld metals, articles having a metal layer and a non-metal layer, and articles having two non-metal layers.

Fig. 2 shows an exploded view of article 100. As shown in fig. 2, substrate 110 may include a substrate bonding surface 112 and a substrate outer surface 114. Additionally, the cladding 120 may include a cladding bonding surface 122 and a cladding outer surface 124. When the base layer 110 and the cladding layer 120 are bonded together, either of the base layer outer surface 114 and the cladding layer outer surface 124 may be considered a surface of the article 100 for purposes of the embodiments described herein.

Fig. 3 illustrates an exemplary embodiment of a method 300 of identifying a boundary between a sound bond between base layer 110 and clad layer 120 and a weak bond between base layer 110 and clad layer 120 in article 100, as illustrated in fig. 1-2. The term "boundary" may refer to a location in the x-y plane (see fig. 7) where the interface between cladding layer 120 and base layer 110 transitions from a strong bond to a weak bond. In block 302, a total of n locations are identified on the surface of the article 100, n being an integer greater than or equal to 2. FIG. 7 illustrates an exemplary embodiment in which a plurality of locations 162 have been identified within a test region 160 on the clad outer surface 124 of the article 100. Although fig. 7 illustrates the location 162 disposed on the cladding outer surface 124, in alternative exemplary embodiments, the location 162 may be identified on the substrate outer surface 114. The locations 162 may be arranged at a constant spacing between each location 162, or there may be different spacings between the locations 162. Additionally, in an exemplary embodiment, only a sub-region of the test article 100 may be required, and the location 162 may be identified only in the test region 160, as shown in FIG. 7. In another exemplary embodiment, it may be desirable to test the entirety of article 100, and location 162 may be identified throughout cladding outer surface 124.

Returning to FIG. 3, in block 304, parameter i is set equal to 1. In block 306, an ith waveform is obtained corresponding to an ith location 162 of the plurality of locations 162. The ith waveform may be a time domain waveform of the intensity of the reflected ultrasonic wave at the ith position. In an exemplary embodiment, the ith waveform may be a full-wave waveform. The full wave waveform is an unrectified waveform of reflected ultrasonic waves, showing positive and negative amplitudes. The first waveform 700 shown in fig. 8 and the second waveform 800 shown in fig. 9 are exemplary embodiments of a full-wave time-domain waveform. Obtaining the ith waveform may include retrieving the waveform from digital memory or obtaining the real-time waveform using an ultrasound transducer. The transducer may be hand-held or may be mounted on an automated system. Table 1 below identifies exemplary embodiments of the types of transducers that may be used and exemplary embodiments of parameters associated with the transducers.

It should be understood that the transducers and parameters listed in table 1 are merely exemplary, and that other types of transducers and/or values for the parameters may be used.

In block 308 of FIG. 3, the (i +1) th waveform is obtained. Similar to the ith waveform, obtaining the (i +1) th waveform may include retrieving the waveform from digital memory, or obtaining the real-time waveform using an ultrasound transducer. In an exemplary embodiment, the same transducer may be used to obtain the ith and (i +1) th waveforms. For example, the transducer may move to the ith position and obtain the ith waveform, and then move to the (i +1) th position and obtain the (i +1) th waveform. The transducer may be moved discretely to each position, or may be moved continuously through each position and acquire waveforms while moving.

In block 310, the ith waveform is compared to the (i +1) th waveform, and in block 312, it is determined whether the comparison performed in block 310 indicates a boundary between a healthy bond between the base layer 110 and the clad layer 120 and a weak bond between the base layer 110 and the clad layer 120 (see fig. 1-2). Further details regarding the comparison in block 310 and the determination in block 312 will be explained in detail herein. If the comparison does indicate a binding boundary (i.e., "yes" at block 312), the method 300 proceeds to block 314. If the comparison does not indicate a join boundary (i.e., "no" at block 312), the method 300 proceeds to block 316.

In block 314, the location of the junction boundary is determined based on one or both of the ith location and the (i +1) th location. For example, FIG. 10 shows a graph having a coordinate of x₁、y₁And has a coordinate x₂、y₂Example of second position 172. The boundary location 174 between the first location 170 and the second location 172 may have the coordinate x_b、y_b. X coordinate x of boundary location 174_bCan fall within the range [ x ]₁、x₂]Inner (including end points), and y-coordinate y of boundary location 174_bCan fall within the range [ y₁、y₂]Inner (including end points). In an exemplary embodiment, the coordinates of the boundary location 174 may be set to the midpoint between the first location 170 and the second location 172. Alternatively, the coordinates of the boundary location 174 may be set anywhere between the first location 170 and the second location 172 and include the first location 170 and the second location 172 depending on the user's preference and needs.

In block 315, the boundary position is recorded. In an exemplary embodiment, the recording may be manual. For example, when the comparison of the waveforms indicates a bond boundary, a user inspecting article 100 (see fig. 1-fig.) using the transducer may mark cladding outer surface 124 with a writing instrument, a portable surface printer, or another suitable marking instrument. Alternatively, if an automated system is used, the system may include a writing instrument, surface printer, laser etcher, or other suitable marking tool to physically mark the boundary locations on the article 100. Alternatively, the recording of the boundary position may include electronically storing coordinates of the boundary position as data in a storage medium.

In block 316, it is determined whether parameter i is equal to the value n-1. If i is equal to n-1 ("yes" in block 316), the method 300 proceeds to block 320 where the method ends in block 320. If i is not equal to n-1 ("NO" of block 316), the method 300 proceeds to block 318, where i is incremented by 1. The method 300 then returns to block 306.

Fig. 4 illustrates another exemplary embodiment of a method 400, the method 300 identifying a boundary between a sound bond between a base layer 110 and a clad layer 120 and a weak bond between the base layer 110 and the clad layer 120 in an article 100, as illustrated in fig. 1-2. As will be explained in detail herein, the method 400 obtains waveforms at all locations 162 and then cycles through the waveforms to compare them. This may be beneficial when using an automated system that can electronically store the waveforms in a storage medium, as the boundary locations can later be calculated and linked to the identification information (e.g., serial number or lot number) of the article under test. This will facilitate higher throughput of the automated system by eliminating the time required to compare waveforms and physically mark boundary locations on the artefact.

In block 402, a total of n locations are identified on the surface of the article 100, n being an integer greater than or equal to 2. In block 404, parameter i is set equal to 1. In block 406, a transducer (e.g., one of the transducers described in table 1 or another suitable transducer) is moved to the ith of the n positions. In block 408, an ultrasonic wave is transmitted through the article 100 via the transducer. In block 410, reflected ultrasonic waves are received at the transducer at the ith location. In block 412, an ith waveform corresponding to the ith position is obtained. The ith waveform may be a time domain waveform of the intensity of the reflected ultrasonic wave at the ith position. As part of generating the ith waveform in block 412, the ith waveform may be electronically stored as data in a storage medium.

In block 414, it is determined whether the parameter i is equal to n. If parameter i is not equal to n ("no" at block 414), the method 400 proceeds to block 416. In block 416, the parameter i is incremented by 1, and the method 400 returns to block 406. If the parameter i is equal to n ("yes" at block 414), the method 400 proceeds to block 418.

In block 418, parameter i is reset to 1. In block 420, the ith waveform is compared to the (i +1) th waveform. As part of block 420, it may be desirable to retrieve the ith and (i +1) th waveforms from electronic memory. In block 422, it is determined whether the comparison performed in block 420 indicates a binding boundary. Further details regarding the comparison in block 420 and the determination in block 422 will be explained in detail herein. If the comparison does indicate a binding boundary (i.e., "yes" at block 422), the method 400 proceeds to block 424. If the comparison does not indicate a join boundary (i.e., "no" at block 422), the method 400 proceeds to block 426.

In block 424, the boundary position of the bonding boundary is determined. The determination of the binding boundary is similar to the method described above with respect to block 314 of fig. 3. In block 425, the boundary position is recorded. The recording of the join boundary is similar to the method described above with respect to block 315 of fig. 3.

In block 426, it is determined whether parameter i is equal to the value n-1. If i is equal to n-1 ("yes" at block 426), the method 400 proceeds to block 430 where the method 400 ends at block 430. If i is not equal to n-1 ("NO" of block 426), the method 400 proceeds to block 428, where i is incremented by 1. The method 400 then returns to block 420 where the next pair of waveforms is compared in block 420.

FIG. 5 illustrates an exemplary embodiment of a method 500 of comparing characteristics of waveforms and determining whether a bond boundary exists between two points. Method 500 may include elements corresponding to blocks 310 and 312 of fig. 3 or blocks 420 and 422 of fig. 4. In describing the method 500, reference will also be made to the first waveform 700 shown in fig. 8 and the second waveform 800 shown in fig. 9.

Returning to fig. 5, in block 502, a first waveform 700 is obtained. The first waveform 700 may be obtained by using an ultrasound transducer as described in detail above. Alternatively, the first waveform 700 may be retrieved as electronic data from a storage medium.

In block 504, a first number p of peaks (i.e., peaks 710 shown in fig. 8) in the first waveform 700 is counted₁. In an exemplary embodiment, a first number p of peaks in a subset of the first waveform 700 corresponding to a predetermined range 706 of values along the x-axis of the first waveform 700 may be counted₁. The predetermined range 706 may correspond to a value in the time domain in which one desires to see ultrasonic waves reflected from the interface between the cladding 120 and the base layer 110. For example, in an exemplary embodiment, it may be assumed that the transducer is placed on the cladding 120. Knowing the thickness of the cladding 120 and the speed of sound in the material of the cladding 120, it is possible to calculate how long it takes for the ultrasonic wave to travel from the transducer to the interface between the cladding 120 and the base layer 110 and back to the transducer. This time period may be used to calculate the midpoint of the predetermined range 706. The width of the predetermined range 706 may be calculated based on manufacturing tolerances of the thickness of the cladding layer 120 and/or an estimated thickness of the interface between the cladding layer 120 and the base layer 110, and then based on the speed of sound in the material of the cladding layer 120 willThese distance values are converted into corresponding values in the time domain of the waveform. Other factors that may affect the calculation of the midpoint and/or width of the predetermined range may include the type of transducer used (i.e., single element, dual element, delay tip, etc.) and/or the type of ultrasound used (i.e., contact, immersion, water column, etc.). Alternatively or additionally, the user may perform a calibration procedure on the article being tested or a known sample prior to testing in order to determine or confirm the appropriate value of the predetermined range 706. For example, the interface between the cladding 120 and the base layer 110 may be visually identified on the ultrasonic waveform to set the predetermined range 706. For the first waveform 700, using the predetermined range 706, fig. 8 shows a first number p of peaks (labeled 710 in fig. 8)₁Equal to 2.

In another exemplary embodiment, the first number of peaks p₁May be the number of peaks above a predetermined first threshold 702 corresponding to the y-value of the first waveform 700. The predetermined first threshold 702 may be determined based on the power level of the transducer used, the particular materials forming the base layer 110 and the cladding layer 120 (see fig. 1-2), the thicknesses of the base layer 110 and the cladding layer 120, and/or other factors that may affect ultrasonic wave propagation. In an exemplary embodiment, a user may perform a calibration procedure on an article being tested or a known sample prior to testing in order to determine an appropriate level of the first threshold 702. For the first waveform 700, using a first threshold 702, fig. 8 shows a first number p of peaks₁Equal to 2.

Returning to FIG. 5, in block 506, a first number t of valleys (labeled 712 in FIG. 8) in the first waveform 700 is counted₁. In an exemplary embodiment, a first number t of valleys in a subset of the first waveform 700 corresponding to a predetermined range 706 of values along the x-axis of the first waveform 700 may be counted₁. For the first waveform 700, using the predetermined range 706, fig. 8 shows a first number t of valleys (labeled 712 in fig. 8)₁Equal to 1. Alternatively, the first number t of valleys₁May be the number of valleys that is less than the predetermined second threshold 704. In an exemplary embodiment, the second threshold may be the negative of the first threshold 702. Alternatively, the second threshold 704 may be formed based on the power level of the transducer usedThe particular materials of base layer 110 and cladding layer 120 (see fig. 1-2), the thicknesses of base layer 110 and cladding layer 120, and/or other factors that may affect ultrasonic wave propagation are independently determined. In an exemplary embodiment, the user may perform a calibration procedure on the article being tested or a known sample prior to testing in order to determine an appropriate level for the second threshold 704. For the first waveform 700, using the second threshold 704, fig. 8 shows that the first number of valleys t1 is equal to 1.

In block 508, a second waveform 800 corresponding to a different location is obtained in a similar manner as in block 502. In block 510, a second number p of peaks (peaks labeled 810 in fig. 9) of the second waveform 800 is counted in a similar manner as in block 504₂. At a second number p of counting peaks₂Then, a first number p for counting peaks may be used₁A first threshold 702 or a predetermined range 706. In block 512, a second number t of valleys (the valleys labeled 812 in fig. 9) of the second waveform 800 are counted in a similar manner as in block 506₂. At a second number t of count valleys₂Then, the first number t for counting the valleys may be used₁A second threshold 704 or a predetermined range 706.

In block 514, a first number p of peaks is determined₁Whether or not to equal the second number of peaks p₂And a first number t of valleys₁Whether it is equal to the second number of valleys t₂. If both equations are true ("yes" in block 514), the method 500 proceeds to block 516 where it is determined that no join boundary exists in block 516. If either equation is not true ("no" in block 514), the method 500 proceeds to block 518 where it is determined that a join boundary exists in block 518.

FIG. 6 illustrates an exemplary embodiment of a method 600 of comparing characteristics of waveforms and determining whether a bond boundary exists between two points. In fig. 6, blocks 602 to 612 are the same as blocks 502 to 512 in fig. 5. In block 614 of FIG. 6, a first number of peaks, p, is determined₁And whether the first number of troughs t1 is equal to the second number of peaks p₂And a second number t of valleys₂Of the second total number. If the equation in block 614 is true ("yes" in block 614), the method 600 proceeds to block 616 where a determination is made not toA binding boundary exists. If the equation in block 614 is not true ("no" in block 614), the method 600 proceeds to block 618 where a join boundary is determined to exist in block 618.

FIG. 30 illustrates an exemplary embodiment of a method 900 of comparing characteristics of waveforms and determining whether a bond boundary exists between two points. In the above-described method 500 and method 600, the waveform 700 and the waveform 800 are characterized by the number of peaks and valleys. In contrast, the characteristic compared in the method 900 shown in fig. 30 is the component frequency of the waveform determined by the Fast Fourier Transform (FFT).

In block 902, a first waveform 700 is obtained. The acquisition of the first waveform 700 in block 902 may be accomplished in a similar manner as in block 502 of fig. 5 or block 602 of fig. 6. In block 904, a first waveform FFT 750 of the first waveform 700 is calculated, as shown by the solid curve in fig. 31. The first waveform FFT 750 may be generated by a known FFT algorithm.

In block 906, a first peak a is identified₁. First peak value a₁May correspond to the amplitude at the first maximum peak 752 of the first waveform FFT 750 (see fig. 31). While fig. 31 may appear to show two maximum peaks for the first waveform FFT 750, it should be understood that many FFT algorithms will generate symmetric curves when operating on real data sets as opposed to operating on complex data sets. Therefore, it is sufficient to identify only a single first maximum peak 752 of the first waveform FFT 750. In the specific example shown in fig. 31, the first peak value a of the first maximum peak 752₁Is calculated to be 9.04.

In block 908, a second waveform 800 is obtained. The acquisition of the second waveform 800 in block 908 may be accomplished in a similar manner as in block 508 of fig. 5 or block 602 of fig. 6. In block 910, a second waveform FFT 850 of the second waveform 800 is calculated, as shown by the dashed curve in fig. 31. The second waveform FFT 850 may be generated by a known FFT algorithm.

In block 912, a second peak a is identified₂. Second peak a₂May correspond to the amplitude at the second maximum peak 852 of the second waveform FFT 850 (see fig. 31). In the specific example shown in fig. 31, the second peak value a of the second maximum peak 852₂Is calculated as 14.08。

In block 914, a first peak a is determined₁And a second peak value a₂Whether the difference b between is greater than a predetermined FFT threshold. The predetermined FFT threshold may be based on an average variation of peaks in known robust binding samples. For example, if the calibration process determines that a known robust binding sample has a 5% FFT peak variation, the predetermined FFT threshold may be a multiple of that variation. For example, in exemplary embodiments, the predetermined FFT threshold may be 10%, 15%, or 20% or more of the peak value. In an exemplary embodiment, the difference b may be calculated as only the first peak value a₁And a second peak value a₂The straight line difference between them, as given by equation (1):

b＝|a₁-a₂| (1)

in an alternative exemplary embodiment, the difference b may be expressed based on the first peak value a₁Or the second peak a₂Percent difference in weight. For example, the difference b may be given by equation (2):

it should be noted that the denominator in equation (2) may be represented by the second peak value a₂Instead of, or alternatively to, the first peak a₁And a second peak value a₂Average value of (a).

Returning to block 914, if the first peak a is determined₁And a second peak value a₂The difference b therebetween is greater than the predetermined FFT threshold ("yes" in block 914), the method 900 proceeds to block 918 where it is determined that a bonding boundary exists in block 918. If it is determined that the difference b is not greater than the predetermined FFT threshold ("NO" of block 914), the method 900 proceeds to block 916 where it is determined that no bonding boundary exists. In the specific example shown in fig. 31, the difference b is 5.04, or the first peak a₁55.8 percent of the total weight. Assuming a predetermined FFT threshold of 20%, this would indicate that there is a bonding boundary between the location corresponding to the first waveform 700 and the location corresponding to the second waveform 800.

In the method 900 described above, the peaks of the FFT waveforms are compared. However, it should be understood that other characteristics of the FFT waveform may also be compared. For example, in an exemplary embodiment, the values at a predetermined interval (bin) of the FFT waveform may be compared instead of the values at the peak. Alternatively, in an exemplary embodiment, the x-axis values of the peaks of the FFT waveforms (i.e., peak positions) may be compared. If the peak positions of the two FFT waveforms vary by more than a predetermined number of intervals, it can be determined that a combination boundary exists between points corresponding to the two FFT waveforms.

Fig. 11-12 illustrate an exemplary embodiment of a system 200 for identifying a bond boundary between a sound bond and a weak bond in an article 100 having a first layer and a second layer. As shown in fig. 11, the system may include a first rail 210, a first rail mount 212, a second rail 220, a tool head 222, an ultrasonic transducer 232, and a controller 240. In an exemplary embodiment, the system 200 may also include a marking device 234.

The second rail 220 may be mounted on the first rail 210 via a first rail mount 212. The system may further include one or more first track mount motors 214 (see fig. 12), the first track mount motors 214 configured to move the first track mount 212 in the y-direction along the first track 210, thereby moving the second track 220 in the y-direction as a result of the second track 220 being mounted on the first track 210 via the first track mount 212. The system 200 may also include one or more position sensors, such as a first track mount encoder 216 (see fig. 12) operatively coupled to the first track mount motor 214. The first track mount encoder 216 may be configured to output an encoder signal indicative of a position of the first track mount 212 along the first track 210 in the y-direction.

The system 200 may further include a tool head motor 224 (see fig. 12), the tool head motor 224 configured to move the tool head 222 along the second track 220 in the x-direction. The system 200 may further include a position sensor, such as a tool head encoder 226 operatively coupled to the tool head motor 224 (see fig. 12). The tool head encoder 226 may be configured to output an encoder signal indicative of the position of the tool head 222 along the second track 220 in the x-direction.

In other words, the first track mount motor 214 and the tool head motor 224 may be part of a motor system that is operably coupled to the tool head 222 and configured to move the tool head 222 along a two-dimensional plane parallel to the surface of the article 100. The first track mount encoder 216 and the tool head encoder 226 are exemplary embodiments of encoders operatively coupled to the motor system and configured to output encoder signals indicative of the position of the tool head 222.

The ultrasonic transducer 232 may be mounted on the tool head 222 in a fixed position relative to the tool head 222. Thus, the position of the ultrasonic transducer 232 may be calculated based on the position of the tool head 222 calculated from the encoder signal. Additionally, the marking device 234 may be mounted on the tool head 222 in a fixed position relative to the tool head 222. Thus, the position of the marking device 234 may be calculated based on the position of the tool head 222 calculated from the encoder signal. The marking device 234 may be any device suitable for marking the surface of an article under test. Non-limiting examples of marking device 234 may include a pen, a surface printer, a laser etcher, or another suitable marking tool for physically marking the boundary location on article 100.

As shown in fig. 12, the controller 240 may be operatively coupled to the ultrasonic transducer 232, the first track mount motor 214, the first track mount encoder 216, the tool head motor 214, the tool head encoder 226, and the marking device 234 via a bus 250. Alternatively, the controller may be configured to wirelessly communicate with the ultrasonic transducer 232, the first track mount motor 214, the first track mount encoder 216, the tool head motor 214, the tool head encoder 226, and the marking device 234 via radio signals, bluetooth, wireless LAN, or other suitable wireless communication method.

As further seen in fig. 12, the controller 240 may include a processor 240a and a memory 240 b. The controller 240 may also be operatively coupled to an external storage medium 242. Additionally, for purposes of this disclosure, the controller 240 may also be considered to be operably coupled to the memory 240 b. The memory 240b and the external storage medium 242 may be non-transitory computer-readable storage media. The processor 240a of the controller 240 may be configured to execute computer-executable instructions stored on any of the memory 240b and/or the external storage medium 242.

The memory 240b and the external storage medium 242 are examples of computer readable media. Computer readable media can be any available media that can be accessed by the computer and includes both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media may include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a computer. Communication media embodies one or more of computer readable instructions, data structures, program modules, etc. and/or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any known information delivery media consistent with the present disclosure. The term "modulated data signal" means a signal that: one or more characteristics of which are set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, Radio Frequency (RF), infrared and other wireless media. Combinations of any of the above should also be included within the scope of computer readable media.

In an exemplary embodiment, the controller 240 may be configured to control the first track mount motor 214 and the tool head motor 224 to move the transducer 232 to a plurality of positions 162 (see fig. 7) along the surface of the article 100. While fig. 11 shows the transducer 232 moving along the outer cladding surface 124 of the article 100, it will also be understood that the transducer 232 may move along the substrate outer surface 114 of the article 100.

The controller 240 may also be configured to identify, for each position 162 of the plurality of positions 162, coordinates of the position based on the encoder signal from the first rail mount encoder 216 and the encoder signal from the tool head encoder 226 based on the fixed relationship between the transducer 232 and the tool head 222. In an exemplary embodiment, the coordinates may be calculated relative to a coordinate system that is inherent to system 200. In another exemplary embodiment, the controller 240 may be configured to calculate coordinates relative to the index mark 190 disposed on the surface of the article 100.

The controller 240 may also be configured to control the transducer 232 to transmit ultrasonic waves through the article 100. The transducer 232 may be configured to receive reflected ultrasonic waves, such as waves reflected from the cladding outer surface 124, waves reflected from the interface between the cladding 120 and the substrate 110, and/or waves reflected from the substrate outer surface 114 (i.e., the back wall). The controller 240 may also be configured to generate a full-wave time-domain waveform, such as the first waveform 700 shown in fig. 8 or the second waveform 800 shown in fig. 9, based on the reflected ultrasonic waves received by the transducer 232. In an exemplary embodiment, the controller 240 may store the waveform in the memory 240b or the storage medium 242 as waveform data associated with a location on the surface of the article 100 at which the waveform was recorded.

The controller 240 may be further configured to, for each pair of adjacent locations of the plurality of locations 162, determine whether a bonding boundary exists between a first location of the pair and a second location of the pair. For example, fig. 10 illustrates an exemplary embodiment of a pair of adjacent locations including a first location 170 and a second location 172, and the controller 240 may be configured to determine whether a bonding boundary exists between the first location 170 and the second location 172. The controller 240 may do this by comparing the waveform characteristics of the first waveform 700 recorded at the first location 170 with the waveform characteristics of the second waveform 800 recorded at the second location 172. In an exemplary embodiment, the controller may determine whether a bonding boundary exists between the first location 170 and the second location 172 by implementing any of the method 500 as described in fig. 5, the method 600 as described in fig. 6, or the method 900 as described in fig. 30.

The controller 240 may be further configured to determine boundary coordinates based on one or both of the first location and the second location in response to determining that a bonding boundary exists between the first location 170 and the second location 172. For example, the controller 240 may be configured to set the coordinates of the boundary location as the coordinates of the first location 170, the coordinates of the second location 172, or the coordinates calculated from both the first location 170 and the second location 172. For example, in the exemplary embodiment shown in FIG. 10, the coordinates of the boundary location 174 are calculated as the midpoint between the first location 170 and the second location 172.

In an exemplary embodiment, once the coordinates of the boundary locations 174 are determined by the controller 240, the user may manually mark the coordinates of the boundary locations 174 on the surface of the article 100 being tested. The area around the coordinates of the boundary location 174 may be further tested in detail by hand to determine the full extent of the weakened bond area in the article 100. Alternatively, in an exemplary embodiment, the controller 240 may be configured to record the coordinates of the boundary location 174. For example, the controller 240 may be configured to control the marking tool 234 to mark the surface of the article 100 at points corresponding to the boundary coordinates. Whether marking is performed manually by a user or automatically by the system 200 via the marking tool 234, the collection of markings 125 may indicate a weak bond area once the test is complete (see fig. 13). In an exemplary embodiment, it may be assumed that the smaller area marked by indicia 125 may be a weak bond area, while the larger remaining area corresponds to a healthy bond.

In an exemplary embodiment, as an alternative to or in addition to marking the article 100, the controller 240 may be configured to record the boundary coordinates by storing the boundary coordinates as electronic data in the memory 240b or the storage medium 242. The stored boundary coordinates may be used for subsequent processing of the article, for example, the machine tool may be programmed to cut away the portion of the article 100 defined by the boundary coordinates to cut away the weakened bond region. Additionally, storing the boundary coordinates as electronic data may allow the boundary location to be mapped onto an image of article 100 on a computer display. In another exemplary embodiment, areas of article 100 identified as having weak bonds may be repaired, if possible.

While the system 200 is described above as employing the first rail encoder 216 and the tool head encoder 226, it should be understood that the system 200 is not limited to encoders for determining the position of the tool head 222. For example, other position detection sensors such as photogrammetric sensors or laser sensors may be used. Alternatively, a retroreflector may be positioned on the tool head 222 for use with a laser metrology system.

Additionally, the system 200 is described above with reference to the tool head 222 moving along the first track 220 and the second track 220. However, the system 200 is not limited to this embodiment. For example, in an alternative embodiment, the tool head 222 may be mounted on an articulated arm having multiple degrees of freedom in order to move the tool head to each desired location on the surface of the article 100.

Fig. 14-29 are images illustrating portions of a clad article identified as a sound bond and portions identified as a weak bond using one or more of methods 300, 400, 500, 600, and 900 described above. In fig. 14 to 29, the product 100 has a base layer 110 made of stainless steel and a cladding layer 120 made of babbitt metal. The cladding 120 is bonded to the base layer 110 by explosion welding.

Fig. 14-17 are low magnification optical micrographs of the substrate bonding surface 112 and the cladding bonding surface 122. In fig. 14, a coherent cladding bond wave 126 is shown corresponding to the cladding bond surface 122 in the sound bond region. Similarly, in FIG. 15, a coherent substrate bond wave 116 is shown corresponding to substrate bonding surface 112 in the sound bonding region. In contrast, in fig. 16, a non-coherent cladding bond wave 128 is shown corresponding to cladding bond surface 122 in the weakened bond region, and in fig. 17, a non-coherent base bond wave 118 is shown corresponding to base bond surface 112 in the weakened bond region. The non-coherent bond waves 118, 128 indicate weak bond areas.

Fig. 18-21 are low magnification optical micrographs of the substrate bonding surface 112 and the cladding bonding surface 122. In fig. 18, which corresponds to cladding bond surface 122 in the sound bond region, and in fig. 19, which corresponds to base bond surface 112 in the sound bond region, there are no visible defects. In contrast, in fig. 20, which corresponds to the clad bond surface 122 in the weakened bond region, and in fig. 21, which corresponds to the base bond surface 112 in the weakened bond region, a circular defect 130 is shown indicating the weakened bond region.

Fig. 22-25 are Scanning Electron Microscope (SEM) micrographs of the area of the cladding bonding surface 122 in the sound bonding area. The surface blurring appearance and limited microcracking in fig. 22-25 indicate a sound bond. In contrast, fig. 26-29 are SEM micrographs of the area of the cladding bonding surface 112 in the weakened bonding region. As seen in fig. 26-29, there are significant microporosities indicated by voids 140, significant cracks 142, rounded and/or elliptical structures 144, and severe corner features 146, all of which indicate weak bond areas.

Thus, in the views of fig. 14-29, the methods described herein successfully non-destructively identify regions of healthy and weak bonding, as subsequently demonstrated by detailed inspection of the bonding surfaces.

In various embodiments, configurations, and aspects, the present disclosure includes components, methods, processes, systems, and/or apparatus as depicted and described herein, including various embodiments, subcombinations, and subsets thereof. In various embodiments, configurations, and aspects, the present disclosure contemplates the actual or alternative use or inclusion of components or processes, for example, that are known or understood in the art and are consistent with the present disclosure, although not shown and/or described herein.

Embodiments of the disclosure are operational with numerous other general purpose or special purpose computing system environments or configurations. Examples of computing systems, environments, and/or configurations that may be suitable for use with the systems and methods described herein include, but are not limited to, personal computers, server computers, hand-held or laptop devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like.

Embodiments of the disclosure may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules may include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The systems and methods described herein may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices. Tasks performed by the programs and modules are described below and with the aid of figures. Those skilled in the art may implement the exemplary embodiments as processor-executable instructions, which may be written on any form of computer-readable media in a corresponding computing environment in accordance with the present invention.

The phrases "at least one," "one or more," and/or "are open-ended expressions that are conjunctive and disjunctive in operation. For example, each of the expressions "at least one of A, B and C", "at least one of a, B, or C", "one or more of A, B and C", "one or more of A, B or C", and "A, B, and/or C" means a alone, B alone, C, A and B, A and C, B and C alone, or a and B and C together.

In this specification and the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings. The terms "a" (or "an") and "the" refer to one or more of the entity and thus include plural references unless the context clearly dictates otherwise. Thus, the terms "a" (or "an"), "one or more" and "at least one" are used interchangeably herein. Furthermore, references to "one embodiment," "some embodiments," "an embodiment," etc., are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as "about," is not to be limited to the precise value specified. In some cases, the approximating language may correspond to the precision of an instrument for measuring the value. Terms such as "first," "second," "upper," "lower," and the like are used to distinguish one element from another, and unless otherwise noted, are not intended to imply a particular order or number of elements.

As used herein, the terms "may" and "may be" denote the possibility of occurring in a set of circumstances; possess a particular attribute, feature or function; and/or qualify another verb by expressing one or more of a capability, or possibility associated with the qualified verb. Thus, usage of "may" and "may be" indicates that the modified term is apparently appropriate, capable, or suitable for the indicated capacity, function, or usage, while taking into account that in some cases the modified term may sometimes not be appropriate, capable, or suitable. For example, in some cases, an event or capacity may be expected, while in other cases it may not occur, and this distinction is reflected by the terms "may" and "may be".

As used in the claims, the word "comprise" and its grammatical variants also logically include different and varying degrees of phrase, such as but not limited to, "substantially by. . . Make up of. . . Composition ". Where necessary, ranges have been provided, and such ranges include all subranges therebetween. It is intended that the appended claims cover all such variations as fall within the scope of the disclosure, unless the disclosure expressly contemplates the use of the particular scope in certain embodiments.

The terms "determine," "calculate," and "compute," and variations thereof, as used herein, are used interchangeably and include any type of method, process, mathematical operation, or technique.

The disclosure has been presented for purposes of illustration and description. The present disclosure is not intended to be limited to the form or forms disclosed herein. In particular embodiments of the present disclosure, for example, where various features of some example embodiments are grouped together to representatively describe these and other contemplated embodiments, configurations and aspects, it is not feasible to include a description of each and every potential embodiment, variation or combination of features in the present disclosure. Thus, features of the disclosed embodiments, configurations, and aspects may be combined in alternative embodiments, configurations, and aspects that are not explicitly discussed above. For example, less than all features of a single disclosed embodiment, configuration or aspect may be recited in the appended claims. Thus, the following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate embodiment of the disclosure.

Advances in science and technology may provide variations that are not necessarily expressed in the terms of this disclosure, but are not necessarily excluded by the claims.