阅读说明：本技术 一种碳纤维增强复合材料褶皱缺陷的涡流检测系统 (A kind of eddy detection system of carbon fibre reinforced composite wrinkle defect ) 是由 王晓红 杨凡 程仿 于 2019-09-03 设计创作，主要内容包括：本发明公开一种碳纤维增强复合材料褶皱缺陷的涡流检测系统,其包括：涡流探头、激励线圈、接收线圈、旋转机构、数控位移平台、计算机、高频函数信号发生器、信号放大器、幅度相位检测器、幅度采集器、相位采集器。本发明中,接收线圈所在平面与激励线圈的中轴线共面,使得涡流探头的输出只受涡流场分布的影响,而不受激励电磁场的影响。本发明不但可以通过涡流信号的幅度增益来检测缺陷的有无,还可以通过相位差的变化来判断褶皱缺陷的类型。尤其是,所设计的涡流探头对碳纤维增强复合材料中的褶皱缺陷特别敏感,而对冲击、断裂等损伤型缺陷不敏感。(The present invention discloses a kind of eddy detection system of carbon fibre reinforced composite wrinkle defect comprising: eddy current probe, excitation coil, receiving coil, rotating mechanism, numerical control displacement platform, computer, high frequency function signal generator, signal amplifier, amplitude-phase detector, amplitude collector, phase acquisition device.In the present invention, plane where receiving coil is coplanar with the central axes of excitation coil, so that the output of eddy current probe is only influenced by vortex field distribution, without the influence of excited target electromagnetic field.The present invention not only can detect the presence or absence of defect by the amplitude gain of eddy current signal, and the type of wrinkle defect can also be judged by the variation of phase difference.Especially, designed eddy current probe is especially sensitive to the wrinkle defect in carbon fibre reinforced composite, and insensitive to impact, fracture equivalent damage type defect.)

1. a kind of eddy detection system of carbon fibre reinforced composite wrinkle defect, characterized in that it comprises: vortex is visited Head, rotating mechanism (2), numerical control displacement platform (3), computer (4), high frequency function signal generator (5), signal amplifier (6), Amplitude-phase detector (7), amplitude collector (8), phase acquisition device (9), wherein

In eddy current probe (1) installation rotating mechanism (2), being able to achieve eddy current probe (1), 360o is rotated in the horizontal plane；

The rotating mechanism (2) is mounted on the sliding block of numerical control displacement platform (3), makes eddy current probe (1) and carbon fiber to be measured Enhance and generates relative position movement between composite material surface；

The numerical control displacement platform (3) is connect by control bus with computer (4), and computer (4) can be by numerical control position It moves platform (3) and sends motion control signal to control the motion profile of eddy current probe (1)；

The pumping signal that the high frequency function signal generator (5) generates divides two-way to export: output access eddy current probe all the way (1), excitation eddy current probe (1) forms vortex in carbon fibre reinforced composite to be measured；Another output accesses amplitude-phase Converter, the reference signal of the extraction as amplitude-phase；

The input terminal of the signal amplifier (6) is connect with the output end of eddy current probe (1), for defeated to eddy current probe (1) Weak swirl signal out amplifies；The input terminal of amplified eddy current signal access amplitude-phase converter (7)；

The amplitude-phase converter (7) compares amplified eddy current signal with reference signal, is converted to above-mentioned The amplitude gain G and phase difference θ of two signals；

The input terminal of the amplitude collector (8) is connected with amplitude-phase converter (7), and amplitude gain G is converted to number Signal is simultaneously uploaded to computer by bus；

The input terminal of the phase acquisition device (9) is connected with amplitude-phase converter (7), and phase difference θ is converted to digital letter Number and computer is uploaded to by bus；

The amplitude collector (8) or phase acquisition device (9) be independent in collector or multi-path collector some solely Vertical channel.

2. a kind of eddy detection system of carbon fibre reinforced composite wrinkle defect as described in claim 1, feature exist In,

The eddy current probe (1) is made of excitation coil (11) and receiving coil (12)；

The excitation coil (11) is parallel to carbon fibre reinforced composite surface to be measured, for multiple in fibre reinforced to be measured The vortex field being accordingly distributed is inspired in condensation material；

Plane where the receiving coil (12) is coplanar with the central axes of excitation coil (11), and multiple with fibre reinforced to be measured Condensation material surface is vertical.

3. a kind of detection of the eddy detection system of carbon fibre reinforced composite wrinkle defect as claimed in claim 1 or 2 Method, characterized in that it comprises the following steps:

Step 1: the predetermined scanning path of eddy current probe (1) is determined according to the region of carbon fibre reinforced composite to be detected；

Step 2: eddy current probe (1) is moved to above carbon fibre reinforced composite to be detected, and rotation rotating mechanism (2) makes carbon Fleece-laying direction is to the left relative to probe orientation；At this point, making its output by the polarity for exchanging receiving coil (12) output end Eddy current signal and the same phase of pumping signal, i.e. phase difference θ=0o；The probe orientation is that excitation coil (11) arrive receiving coil (12) center line connecting direction；

Step 3: rotating rotating mechanism (2) again is laid with the probe orientation of eddy current probe (1) and carbon fibre reinforced composite Direction is consistent；

Step 4: numerical control displacement platform (3) are controlled by computer (4), make eddy current probe (1) by predetermined scan path in carbon fiber Dimension enhancing composite material surface relative movement, carries out scanning；

Step 5: synchronously, computer (4) is read out amplitude collector (8) and phase acquisition device (9) by bus, obtains Take the amplitude gain G and phase difference θ of eddy current signal at different location；

Step 6: amplitude gain G resulting to step 5 carries out on-line analysis:

If G < G0, illustrate zero defect at the position, return step five reads next group of data；The G0 is to need system point Amplitude gain corresponding to the minimum wrinkle defect distinguished；

Otherwise, as G >=G0, then illustrate existing defects at the position, carry out step 7；

Step 7: on-line analysis is carried out to phase difference θ obtained in step 5, to judge the type of wrinkle defect；In certain region, If phase difference θ is first 0o, then is changed as 180o, then it can determine whether a wrinkle defect to the left occur below eddy current probe (1), It is first curved to the left then curved to the right；Conversely, if phase difference θ is first 180o, then change as 0o, then can determine whether to go out below eddy current probe (1) Show a wrinkle defect to the right, it is first curved to the right then curved to the left.

Technical field

The detection system more particularly to a kind of needle that the present invention relates to a kind of for detecting carbon fibre reinforced composite defect To the eddy detection system of carbon fibre reinforced composite wrinkle defect, belong to the electromagnetic nondestructive field of composite material.

Background technique

Carbon fibre reinforced composite has high intensity, the comprehensive advantages such as high fatigue durability and extremely low weight, it has also become boat The important candidate material in the fields such as empty space flight, ship and vehicle structure.Since carbon fibre reinforced composite is laminate structures, institute Material property is caused to fail to be easy to appear layering, fold and other issues in the fabrication process.Currently, according to such material Different characteristics, be applied there are many non-destructive testing technology.Due to carbon fibre reinforced composite be using carbon fiber as The composite material of reinforcement, it is conductive, it is possible to be carried out non-destructive testing by eddy detection technology.

Chinese patent CN104914158B discloses a kind of high-frequency electromagnetic whirlpool for carbon fibre composite damage check Flow detection system, including host computer, displacement platform, eddy current probe, analogy signal processing unit and digital signal processing unit.It should Invention can be measured in real time the damage of carbon fibre composite in high frequency 10MHz.

A kind of carbon fiber resin matrix composite intermediate-frequency vortex detection system disclosed in 104897775 B of Chinese patent CN, Including signal generating module, currents sensing unit, locking phase amplification module and signal acquisition module.The invention realizes carbon fiber tree The detection and judgement of resin-based composite characteristic and damage.

Chinese patent CN106645391A discloses a kind of for assessing the multi frequency detection of carbon fiber board depth of defect System and detection method.The invention obtains defect ruler by measuring peak induction voltage and the crest frequency of different depth defect Very little information, to realize the assessment of depth of defect in multiple material plate.

Chinese patent CN106546657A discloses a kind of vortex spy for detecting carbon fibre composite laying direction Head annular Array Method.The invention combines linear transducer array method and Near resonance oscillating frequency working method carries out probe signal induced voltage It extracts, the information in carbon fiber layer plywood laying direction is showed with polar form, can accurately and effectively realize that carbon fiber is multiple The judgement of condensation material laminate laying.

By relevant report, at present for the non-destructive testing of carbon fibre reinforced composite mainly still concentrate on impact, It is broken in the flaw detection of equivalent damage type defect.And the wrinkle defect for occurring in manufacturing process, still lack single-minded, effective nothing Damage detection means.

Summary of the invention

It is an object of the invention to provide a kind of simple and convenient, smart for wrinkle defect in carbon fibre reinforced composite Really efficient eddy detection system and its detection method.

To achieve the above object, the present invention adopts the following technical scheme:

A kind of eddy detection system of carbon fibre reinforced composite wrinkle defect, comprising: eddy current probe, rotating mechanism, numerical control Displacement platform, computer, high frequency function signal generator, signal amplifier, amplitude-phase detector, amplitude collector, phase Collector, wherein

, it can be achieved that eddy current probe 360o rotation in the horizontal plane on the eddy current probe installation rotating mechanism；The vortex Probe is made of excitation coil and receiving coil；

The excitation coil is parallel to carbon fibre reinforced composite surface to be measured, corresponding for inspiring in detected materials The vortex field of distribution；Plane where the receiving coil is coplanar with the central axes of excitation coil, and with fibre reinforced to be measured Composite material surface is vertical.

The rotating mechanism is mounted on the sliding block of numerical control displacement platform, makes eddy current probe and fibre reinforced to be measured It is mobile that opposite position is generated between composite material surface.

The numerical control displacement platform is connect by control bus with computer, can be transported by sending to numerical control displacement platform Dynamic signal generates opposite motion profile to control eddy current probe and carbon fibre reinforced composite surface.

The pumping signal that the high frequency function signal generator generates has two-way output, and output connects eddy current probe all the way, Eddy current probe is set to form vortex in carbon fibre reinforced composite to be measured；Another output connects amplitude-phase converter, is The extraction of amplitude-phase provides reference signal.

The input terminal of the signal amplifier is connect with receiving coil, the weak swirl letter for picking up to eddy current probe It number amplifies；The input terminal of amplified eddy current signal access amplitude-phase converter.

The amplitude-phase converter compares amplified eddy current signal and reference signal (pumping signal), turns Get the amplitude gain G and phase difference θ of above-mentioned two signal in return.

The amplitude collector input terminal is connected with amplitude-phase converter, and amplitude gain G is converted to digital signal And computer is uploaded to by bus.

The phase acquisition device input terminal is connected with amplitude-phase converter, and phase difference θ is converted to digital signal simultaneously Computer is uploaded to by bus.Amplitude collector or phase acquisition device can be independent collector, are also possible to multichannel and adopt Some autonomous channel in storage.

Relative to traditional eddy current probe, there are two clear advantages for the eddy current probe designed in the present invention: first, it receives Plane where coil is coplanar with the central axes of excitation coil, so that the excitation electromagnetic field that excitation coil generates does not pass through reception line It encloses, the mutual inductance between two coils is always zero.Therefore eddy current probe stable output signal in the present invention, only by vortex field distribution It influences, without the influence of excited target coil stimulating electromagnetic field.Second, receiving coil and carbon fibre reinforced composite table to be measured Face is vertical, and eddy current signal only can be just induced in receiving coil there are when vortex field immediately below receiving coil.

In the detection process, probe orientation should be kept consistent with carbon fiber laying direction first.The probe orientation is just It is center line connecting direction of the excitation coil to receiving coil.It, can be to vortex due to the anisotropy of carbon fibre material electric conductivity Field is laid with direction along carbon fiber and is stretched.At this point, centre of the receiving coil just at the vortex field that is stretched, therefore receive line Circle is exported without eddy current signal.If there are folds in process of deployment for carbon fiber, it is meant that the carbon fiber direction hair at fold It is raw to change.As shown in Figure 3, it is assumed that detected carbon fiber is suddenly bending to the left, correspondingly occurs one immediately below receiving coil A Eddy Distribution from right to left, then receiving coil will also induce accordingly eddy current signal.And defect is impacted or is broken, but not It will cause the variation of vortex field distribution immediately below receiving coil.Therefore, the eddy current probe designed in the present invention, to fibre reinforced Wrinkle defect in composite material is especially sensitive, and insensitive to impact, fracture equivalent damage type defect.

A kind of detection method of the eddy detection system of carbon fibre reinforced composite wrinkle defect, which is characterized in that make With including the following steps: in the process

Step 1: the predetermined scanning path of eddy current probe is determined according to the region of carbon fibre reinforced composite to be detected.

Step 2: eddy current probe is moved to above carbon fibre reinforced composite to be detected, and rotation rotating mechanism makes carbon fiber It is to the left relative to probe orientation that dimension is laid with direction.At this point, making the eddy current signal of its output by the output end for exchanging receiving coil With the same phase of pumping signal, i.e. phase difference θ=0o.

Step 3: rotating rotating mechanism again keeps the probe orientation of eddy current probe consistent with carbon fiber laying direction.

Step 4: controlling numerical control displacement platform by computer, makes eddy current probe by predetermined scan path, increases in carbon fiber Strong composite material surface relative movement, carries out scanning.

Step 5: meanwhile, computer is read out amplitude collector and phase acquisition device by bus, obtains different positions Set the amplitude gain G and phase difference θ of place's eddy current signal.

Step 6: amplitude gain G resulting to step 5 carries out on-line analysis.

If G < G0, illustrate zero defect at the position, return step five reads next group of data；The G0 be need be Amplitude gain corresponding to the minimum wrinkle defect that system is differentiated；

Otherwise, i.e. G >=G0 then illustrates existing defects at the position, carries out step 7.

Step 7: on-line analysis is carried out to phase difference θ obtained in step 5, to judge the type of wrinkle defect.At certain Region then can determine whether that occurring a fold to the left below eddy current probe lacks if phase difference θ is first 0o, then is changed as 180o Fall into (first curved to the left then curved to the right)；Conversely, if phase difference θ is first 180o, then change as 0o, then can determine whether below eddy current probe There is a wrinkle defect (first curved to the right then curved to the left) to the right.

From the above mentioned it is found that the invention has the benefit that realizing the inspection of carbon fibre reinforced composite wrinkle defect It surveys and judges.Within the system, not only the presence or absence of defect can be detected by the amplitude gain G of eddy current signal, can also led to The variation of phase difference θ is crossed to judge the type of wrinkle defect.Especially, designed eddy current probe is to carbon fiber reinforced plastic Wrinkle defect in material is especially sensitive, and insensitive to impact, fracture equivalent damage type defect.

Detailed description of the invention

Fig. 1 is the schematic diagram of present system structure；

Fig. 2 is the structural schematic diagram of eddy current probe in the embodiment of the present invention；

Fig. 3 is in the embodiment of the present invention to the schematic illustration of wrinkle defect detection；

Fig. 4 is schematic diagram insensitive to damage type defect in the embodiment of the present invention.

The description of symbols of each component in figure: 1, eddy current probe；11, excitation coil；12, receiving coil；2, rotating mechanism；3, Numerical control displacement platform；4, computer；5, high frequency function signal generator；6, signal amplifier；7, amplitude-phase detector；8, width Spend collector；9, phase acquisition device；10, carbon fibre reinforced composite.

Specific embodiment

Further technical solution provided by the invention is illustrated with reference to the accompanying drawing.

Referring to Fig. 1, a kind of eddy detection system of carbon fibre reinforced composite wrinkle defect, comprising: eddy current probe 1, Rotating mechanism 2, numerical control displacement platform 3, computer 4, high frequency function signal generator 5, signal amplifier 6, amplitude-phase detection Device 7, amplitude collector 8, phase acquisition device 9.Wherein,

Eddy current probe 1 is mounted on rotating mechanism 2, it can be achieved that the 360o rotation in the horizontal plane of eddy current probe 1；

Rotating mechanism 2 preferably uses RS40 rotary table, and Workbench base is mounted on the sliding block of numerical control displacement platform 3, makes whirlpool It is mobile that opposite position is generated between stream probe 1 and carbon fibre reinforced composite surface to be measured.

Numerical control displacement platform 3 preferably uses two axis rail slide units of 300mm × 400mm area；Stepping electricity is passed through by computer 4 Stepper motor corner on machine driver control guide rail slide unit realizes eddy current probe 1 on carbon fibre reinforced composite surface Scanning campaign.

Computer 4 preferably has the industrial personal computer of NOVA MCX314A four-axis movement control card.

High frequency function signal generator 5 preferably uses DG1022U, and preferably the sine wave of 15MH, 1.0V are as pumping signal；Swash Encouraging signal divides two-way to be accessed in circuit with shielding line terminals: the first via directly drives excitation coil 11, and another way is believed as benchmark Number output is to amplitude-phase converter 7.

Signal amplifier 6 preferably uses TLC2652 amplifier, is set as in-phase amplifier, gain amplifier 40dB.It is put using this The weak swirl signal that big device picks up receiving coil 12 amplifies, and the input of amplitude-phase converter 7 is accessed after amplification End.

The preferred AD8302 module of amplitude-phase converter 5.The module carries out amplified eddy current signal and reference signal Comparison, and export the amplitude gain G and phase difference θ expressed in the form of analog voltage.

The first passage of the preferred USB3210 data collecting card of amplitude collector 8, by first passage input terminal and amplitude-phase Converter 7 is connected, and carries out 16 bit digital conversions to amplitude gain G, and transformation result is uploaded to computer 4 by usb bus.

The second channel of the preferred USB3210 data collecting card of phase acquisition device 9, by second channel input terminal and amplitude-phase Converter 7 is connected, and carries out 16 bit digital conversions to phase difference θ and is uploaded to computer 4 by usb bus.

Referring to fig. 2, eddy current probe 1 is made of excitation coil 11 and receiving coil 12；The preferably thickness 3mm of excitation coil 11, directly The circular coil of diameter 8mm is formed with uniform 60 circle of coiling of the enameled wire of 0.1mm；Preferably thickness 3mm, 8mm × 8mm of receiving coil 12 Square coil is formed with uniform 30 circle of coiling of the enameled wire of 0.1mm.Excitation coil 11 with the lift-off value of 1.0mm, be placed in parallel to The carbon fibre reinforced composite surface of survey.Receiving coil 12 is placed vertically with the lift-off value of 1.0mm, and plane where it It is coplanar with the central axes of excitation coil 11.From figure 2 it can be seen that the excitation electromagnetic field that excitation coil 11 generates is not passed through and is connect Take-up circle 12, therefore receiving coil 12 is only influenced by vortex field distribution.

In Fig. 2, due to the anisotropy of carbon fibre reinforced composite electric conductivity, it is vortexed produced by excitation coil 11 Field can be laid with direction along carbon fibre reinforced composite and be stretched.If the position that excitation coil 11 and receiving coil 12 are put Consistent, then centre of the receiving coil 12 just at the vortex field being stretched that be laid with direction with carbon fibre reinforced composite.Very Obviously, the vortex field distribution of 12 left and right sides of receiving coil is symmetrical balance, therefore defeated without eddy current signal in receiving coil 12 Out.

Referring to Fig. 3, eddy current probe 1 is laid with direction scanning from left to right along carbon fibre reinforced composite.In receiving coil There are wrinkle defect, relative eddy 1 direction of motion of probe, the bending of carbon fiber generation one to the left immediately below 12.At this point, receiving The vortex field of 12 left and right sides symmetrical balance of coil is broken, and an Eddy Distribution from right to left correspondingly occurs.Receive line Circle 12 will also induce accordingly eddy current testing signal, to reach the mesh to the detection of carbon fibre reinforced composite wrinkle defect 's.

Referring to fig. 4, if there is impact, fracture equivalent damage type defect in the scanning approach of eddy current probe 1.The type defect Only it can change the size being vortexed in fault location, and the state of 12 left and right sides symmetrical balance of receiving coil still retains.Therefore, originally The eddy current probe of invention is insensitive to damage type defect.

The detection method of the eddy detection system of one of the present embodiment carbon fibre reinforced composite wrinkle defect, In Include the following steps: in use process

Step 1: carbon fibre reinforced composite to be measured is placed on two axis rail slide units, and determines 1 scan path of eddy current probe To be laid with direction along carbon fiber are as follows: from left to right, from the top down.

Step 2: eddy current probe 1 is moved to above carbon fibre reinforced composite to be detected, rotates RS40 rotary table Carbon fiber is set to be laid with direction to the left relative to probe orientation.If eddy current signal and pumping signal reverse phase, i.e. phase difference θ=180 at this time O then exchanges the polarity of receiving coil 12, the eddy current signal and the same phase of pumping signal, i.e. phase difference θ=0o for exporting it.

Step 3: rotating RS40 rotary table again makes the probe orientation of eddy current probe 1 and carbon fiber be laid with direction one It causes, receiving coil 12 is exported without eddy current signal at this time.The minimum wrinkle defect of system resolution will be needed to be moved to eddy current probe 1 just Lower section, the amplitude gain for recording eddy current signal at this time is G0.

Step 4: two axis rail slide units are controlled by industrial personal computer, move eddy current probe 1 by predetermined scan path, are carried out Scanning.

Step 5: meanwhile, industrial personal computer is by usb bus to the first passage and second channel of USB3210 data collecting card It is read out, obtains the amplitude gain G and phase difference θ of eddy current signal at different location.

Step 6: amplitude gain G resulting to step 5 carries out on-line analysis.

If G < G0, illustrate zero defect at the position, return step five reads next group of data；

Otherwise, i.e. G >=G0 then illustrates existing defects at the position, carries out step 7；

Step 7: on-line analysis is carried out to phase difference θ obtained in step 5, to judge the type of wrinkle defect.In certain region, If phase difference θ is first 0o, then is changed as 180o, then it can determine whether occur a wrinkle defect to the left below eddy current probe 1 (i.e. It is first curved to the left then curved to the right)；Conversely, if phase difference θ is first 180o, then change as 0o, then can determine whether to go out below eddy current probe 1 A wrinkle defect (i.e. first curved to the right then curved to the left) to the right is showed.