阅读说明：本技术 基于斜入射的超声阵列电池箱焊缝全聚焦成像方法 (Oblique incidence-based ultrasonic array battery box weld full-focusing imaging method ) 是由 季胜蓝 徐宋飞 孙美 顾海勤 李洪亮 于 2021-09-02 设计创作，主要内容包括：本发明公开了一种基于斜入射的超声阵列电池箱焊缝全聚焦成像方法,涉及电动车技术领域,本发明基于斯涅尔定律,再结合阵列式的超声波在界面中的传播特性,确定引入楔块下声束的传播路径,并将斜入射超声阵列全聚焦成像技术用于铝质电池箱焊缝缺陷检测,进行全面检测,避免出现漏检现象,根据检测结果可及时了解铝质电池箱焊缝具体情况,同时根据出现的缺陷制定最佳的焊接工艺要求,保证了铝质电池箱的品质,提高新能源汽车的安全性。(The invention discloses an oblique incidence-based ultrasonic array battery box weld joint full-focusing imaging method, which relates to the technical field of electric vehicles and is characterized in that based on Snell's law, the propagation characteristics of array-type ultrasonic waves in an interface are combined, the propagation path of an acoustic beam under an introduced wedge block is determined, the oblique incidence ultrasonic array full-focusing imaging technology is used for detecting the weld joint defects of an aluminum battery box, comprehensive detection is carried out, the missing detection phenomenon is avoided, the specific conditions of the weld joint of the aluminum battery box can be known in time according to the detection result, and meanwhile, the optimal welding process requirement is formulated according to the defects, so that the quality of the aluminum battery box is ensured, and the safety of a new energy automobile is improved.)

1. A full-focusing imaging method for a weld joint of an ultrasonic array battery box based on oblique incidence is characterized by comprising the following steps: the method comprises the following specific steps:

the method comprises the following steps: adding a wedge block on an ultrasonic array probe, counting the number of array elements in the ultrasonic array probe as n, and setting the detection times of the ultrasonic array probe as M groups;

step two: obliquely injecting a main sound beam into a welding seam of a to-be-tested piece through a wedge block, determining that the oblique incidence angle of the main sound beam is theta 1, the refractive index of the wedge block is K1, the refractive index of a material K2 and the refractive index of air K3 after welding and forming at the welding seam, the refractive angle of the obtained material after welding and forming at the welding seam is theta 2 and the refractive angle of air theta 3 in the welding seam, obtaining two corresponding groups of ultrasonic echo signals through an ultrasonic array probe by a processor, recording the emitting time of the material after the main sound beam enters the welding seam and is formed to a first group of ultrasonic echo signals as t1, t2 and … … tn, recording the emitting time of the material after the main sound beam enters the welding seam and is t11, t21 and … … tn1, and drawing point characteristics (X11, Y11), (X21, Y21), … … (Xn1 and Yn1) corresponding to time t1, t2 and T8 tn on a coordinate system and drawing time 11, t21 and … … tn1 obtain point characteristics (X12, Y12), (X22, Y22) and … … (Xn2, Yn 2);

step three: point features of (X11, Y11), (X21, Y21), … … (Xn1, Yn1), (X12, Y12), (X22, Y22), … … (Xn2, Yn2) are connected into a closed curve, obtaining a local ultrasound phased array image P1;

step four: when the second local ultrasonic phased array imaging is carried out, the first array element to the nth array element of the ultrasonic array probe are controlled to simultaneously transmit an ultrasonic signal local ultrasonic phased array image P2;

step five: according to the method of the steps 3 and 4, performing the rest multiple times of ultrasonic phased array local imaging in sequence, and marking the obtained local ultrasonic phased array images as P1, P2 and … … PM respectively;

and 4, step 4: the weld seam is sized to form a negative plate in the processor, and then P1, P2 and … … PM are guided to the negative plate to be synthesized into the full focus imaging of the weld seam of the ultrasonic array battery box at oblique incidence.

2. The oblique incidence-based ultrasonic array battery box weld full-focusing imaging method according to claim 1, characterized in that: the theta 2 is calculated according to the refraction law, and the calculation formula is as follows:

k1sinθ1＝k2sinθ2。

3. the oblique incidence based ultrasonic array battery box weld full focus imaging method according to claim 2, characterized in that: the theta 1 is controlled to be 30-60 degrees.

4. The oblique incidence based ultrasonic array battery box weld full focus imaging method according to claim 2, characterized in that: the calculation formula of θ 3 is as follows:

K3sinθ3＝k2sinθ2。

5. the oblique incidence based ultrasonic array battery box weld full focus imaging method according to claim 4, characterized in that: the calculation formulas of Xn1 and Yn1 in the (Xn1 and Yn1) are as follows:

Xn1＝V2·tn/2·sinθ2；

Yn1＝V2·tn/2·cosθ2；

wherein, V2 is the propagation velocity of the material after the main sound beam is welded and formed at the welding seam.

6. The oblique incidence based ultrasonic array battery box weld full focus imaging method according to claim 5, characterized in that: the calculation formulas of Xn2 and Yn2 in the (Xn2 and Yn2) are as follows:

Xn2＝Xn1+V1·(tn1-tn)/2·sinθ3；

Yn2＝Yn1+V1·(tn1-tn)/2·cosθ3；

where V1 is the propagation velocity of the main beam in air.

7. The oblique incidence based ultrasonic array battery box weld full focus imaging method according to claim 6, characterized in that: the ultrasonic array probe is a longitudinal wave probe.

8. The oblique incidence based ultrasonic array battery box weld full focus imaging method according to claim 7, characterized in that: the shape of the wedge block is adjusted according to the shape of the welding seam of the battery box, so that the wedge block is in welding, laminating and contact with the battery box.

Technical Field

The invention relates to the technical field of electric vehicles, in particular to an oblique incidence-based ultrasonic array battery box weld full-focusing imaging method.

Background

At present, new energy automobiles are vigorously developed in various countries in the world. The development of energy-saving and new energy automobiles is one of the important measures for reducing the petroleum consumption and the carbon dioxide emission.

Under a good development environment, the technology of a pure electric vehicle is changing day by day, and the technical growth of a battery box is changing continuously. The aluminum alloy battery box has light weight, can reduce the weight of the whole vehicle, and has certain effect on the endurance mileage.

The existing battery box is generally formed by welding several aluminum alloy plates, the quality of a welding line determines the quality of the aluminum battery box, the welding line needs to be detected in order to ensure the overall quality of the aluminum battery box, the welding line is manually detected by holding an ultrasonic probe in the prior art, comprehensive detection cannot be carried out, the phenomenon of missed detection is easy to occur, the detection of the aluminum battery box is inaccurate, enterprises cannot adjust the welding scheme to the best, and therefore the quality of the aluminum battery box cannot be ensured.

Therefore, an ultrasonic array battery box welding seam full-focusing imaging method based on oblique incidence is provided to solve the problems.

Disclosure of Invention

The invention aims to provide an oblique incidence-based ultrasonic array battery box weld full-focusing imaging method to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a full-focusing imaging method for a weld joint of an ultrasonic array battery box based on oblique incidence comprises the following specific steps:

the method comprises the following steps: adding a wedge block on an ultrasonic array probe, counting the number of array elements in the ultrasonic array probe as n, and setting the detection times of the ultrasonic array probe as M groups;

step two: obliquely injecting a main sound beam into a welding seam of a to-be-tested piece through a wedge block, determining that the oblique incidence angle of the main sound beam is theta 1, the refractive index of the wedge block is K1, the refractive index of a material K2 and the refractive index of air K3 after welding and forming at the welding seam, the refractive angle of the obtained material after welding and forming at the welding seam is theta 2 and the refractive angle of air theta 3 in the welding seam, obtaining two corresponding groups of ultrasonic echo signals through an ultrasonic array probe by a processor, recording the emitting time of the material after the main sound beam enters the welding seam and is formed to a first group of ultrasonic echo signals as t1, t2 and … … tn, recording the emitting time of the material after the main sound beam enters the welding seam and is t11, t21 and … … tn1, and drawing point characteristics (X11, Y11), (X21, Y21), … … (Xn1 and Yn1) corresponding to time t1, t2 and T8 tn on a coordinate system and drawing time 11, t21 and … … tn1 obtain point characteristics (X12, Y12), (X22, Y22) and … … (Xn2, Yn 2);

step three: point features of (X11, Y11), (X21, Y21), … … (Xn1, Yn1), (X12, Y12), (X22, Y22), … … (Xn2, Yn2) are connected into a closed curve, obtaining a local ultrasound phased array image P1;

step four: when the second local ultrasonic phased array imaging is carried out, the first array element to the nth array element of the ultrasonic array probe are controlled to simultaneously transmit an ultrasonic signal local ultrasonic phased array image P2;

step five: according to the method of the steps 3 and 4, performing the rest multiple times of ultrasonic phased array local imaging in sequence, and marking the obtained local ultrasonic phased array images as P1, P2 and … … PM respectively;

and 4, step 4: the weld seam is sized to form a negative plate in the processor, and then P1, P2 and … … PM are guided to the negative plate to be synthesized into the full focus imaging of the weld seam of the ultrasonic array battery box at oblique incidence.

Further, θ 2 is calculated according to the law of refraction, and the calculation formula is as follows:

k1sinθ1＝k2sinθ2。

further, the theta 1 is controlled to be 30-60 degrees.

Further, the calculation formula of θ 3 is as follows:

K3sinθ3＝k2sinθ2。

further, the calculation formulas of Xn1 and Yn1 in (Xn1 and Yn1) are as follows:

Xn1＝V2·tn/2·sinθ2；

Yn1＝V2·tn/2·cosθ2；

wherein, V2 is the propagation velocity of the material after the main sound beam is welded and formed at the welding seam.

Further, the calculation formulas of Xn2 and Yn2 in (Xn2 and Yn2) are as follows:

Xn2＝Xn1+V1·(tn1-tn)/2·sinθ3；

Yn2＝Yn1+V1·(tn1-tn)/2·cosθ3；

where V1 is the propagation velocity of the main beam in air.

Furthermore, the ultrasonic array probe is a longitudinal wave probe.

Furthermore, the shape of the wedge block is adjusted according to the shape of the welding seam of the battery box, so that the wedge block is in welding, fitting and contact with the battery box.

The invention has the beneficial effects that:

based on Snell's law, the invention combines the propagation characteristics of the array ultrasonic waves in the interface to determine the propagation path of the acoustic beam under the wedge block, applies the oblique incidence ultrasonic array full-focusing imaging technology to the detection of the weld defects of the aluminum battery box to carry out comprehensive detection, avoids the detection omission phenomenon, can know the specific conditions of the weld of the aluminum battery box in time according to the detection result, and simultaneously formulates the optimal welding process requirement according to the defects, thereby ensuring the quality of the aluminum battery box and improving the safety of new energy automobiles.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic diagram of a single-shot local ultrasound phased array image P1 obtained by the ultrasound array probe of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The present invention will be further described with reference to the following examples.

Example 1

A full-focusing imaging method for a weld joint of an ultrasonic array battery box based on oblique incidence comprises the following specific steps:

the method comprises the following steps: adding a wedge block on an ultrasonic array probe, counting the number of array elements in the ultrasonic array probe as n, and setting the detection times of the ultrasonic array probe as M groups;

step two: obliquely injecting a main sound beam into a welding seam of a to-be-tested piece through a wedge block, determining that the oblique incidence angle of the main sound beam is theta 1, the refractive index of the wedge block is K1, the refractive index of a material K2 and the refractive index of air K3 after welding and forming at the welding seam, the refractive angle of the obtained material after welding and forming at the welding seam is theta 2 and the refractive angle of air theta 3 in the welding seam, obtaining two corresponding groups of ultrasonic echo signals through an ultrasonic array probe by a processor, recording the emitting time of the material after the main sound beam enters the welding seam and is formed to a first group of ultrasonic echo signals as t1, t2 and … … tn, recording the emitting time of the material after the main sound beam enters the welding seam and is t11, t21 and … … tn1, and drawing point characteristics (X11, Y11), (X21, Y21), … … (Xn1 and Yn1) corresponding to time t1, t2 and T8 tn on a coordinate system and drawing time 11, t21 and … … tn1 obtain point characteristics (X12, Y12), (X22, Y22) and … … (Xn2, Yn 2);

step three: point features of (X11, Y11), (X21, Y21), … … (Xn1, Yn1), (X12, Y12), (X22, Y22), … … (Xn2, Yn2) are connected into a closed curve, and a local ultrasound phased array image P1 is obtained (as shown in fig. 1);

step four: when the second local ultrasonic phased array imaging is carried out, the first array element to the nth array element of the ultrasonic array probe are controlled to simultaneously transmit an ultrasonic signal local ultrasonic phased array image P2;

step five: according to the method of the steps 3 and 4, performing the rest multiple times of ultrasonic phased array local imaging in sequence, and marking the obtained local ultrasonic phased array images as P1, P2 and … … PM respectively;

and 4, step 4: the weld seam is sized to form a negative plate in the processor, and then P1, P2 and … … PM are guided to the negative plate to be synthesized into the full focus imaging of the weld seam of the ultrasonic array battery box at oblique incidence.

θ 2 is calculated according to the law of refraction, and the calculation formula is as follows:

k1sinθ1＝k2sinθ2。

theta 1 is controlled to be 30-60 degrees.

The calculation formula of θ 3 is as follows:

K3sinθ3＝k2sinθ2。

the calculation formulas of Xn1 and Yn1 in (Xn1 and Yn1) are as follows:

Xn1＝V2·tn/2·sinθ2；

Yn1＝V2·tn/2·cosθ2；

wherein, V2 is the propagation velocity of the material after the main sound beam is welded and formed at the welding seam.

The calculation formulas of Xn2 and Yn2 in (Xn2 and Yn2) are as follows:

Xn2＝Xn1+V1·(tn1-tn)/2·sinθ3；

Yn2＝Yn1+V1·(tn1-tn)/2·cosθ3；

where V1 is the propagation velocity of the main beam in air.

The ultrasonic array probe is a longitudinal wave probe.

The shape of the wedge block is adjusted according to the shape of the welding seam of the battery box, so that the wedge block is in welding, laminating and contact with the battery box.

Based on Snell's law, the propagation characteristics of the array ultrasonic waves in the interface are combined, the propagation path of the acoustic beam under the wedge block is determined, the oblique incidence ultrasonic array full-focusing imaging technology is used for detecting the weld defects of the aluminum battery box, comprehensive detection is carried out, the detection leakage phenomenon is avoided, the specific conditions of the weld of the aluminum battery box can be known in time according to the detection result, meanwhile, the optimal welding process requirement is formulated according to the defects, the quality of the aluminum battery box is ensured, and the safety of the new energy automobile is improved.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.