CN102621227A - Nonlinear ultrasonic evaluation method of metal material plating damage - Google Patents

Abstract

The invention provides a nonlinear ultrasonic evaluation method of metal material plating damage, which relates to metal material plating damage testing so as to determine the damage degree of the plating. The method comprises the following steps of: selecting a plating test piece; testing the plating test piece by using a nonlinear ultrasonic testing system so as to obtain an initial relative nonlinear coefficient; carrying out loading on the plating test piece for five times so as to obtain five loaded stresses; carrying out nonlinear ultrasonic testing on the five loaded plating test pieces so as to obtain five relative nonlinear coefficients; dividing the relative nonlinear coefficients by the initial relative nonlinear coefficient so as to regularize the relative nonlinear coefficients as vertical coordinates; representing the initial and five regularized relative nonlinear coefficient values in a coordinate by using the stresses as horizontal ordinates so as to obtain a relationship curve diagram between the regularized relative nonlinear coefficients and the stresses, wherein damage exists in the plating test piece during regularizing the relative nonlinear coefficient of more than 1 and less than the regularized relative nonlinear coefficient when the plating has a crack; and the larger the relative nonlinear coefficient is and the larger the damage degree is.

Description

The nonlinear ultrasonic evaluation method of metal material coating damage

Technical field

The present invention relates to a kind of nonlinear ultrasonic evaluation method of metal material coating damage, belong to technical field of measurement and test.

Background technology

Plating is exactly to utilize electrolysis principle on some metal surface, to plate the process of other metal or alloy of skim; Be to utilize electrolytic action that thereby the technology of the surface attachment layer of metal film of metal or other material product is played to prevent corrosion, improve wearing quality, electric conductivity, reflective and promote effects such as attractive in appearance.But, because the overlayer of electroplating is different with matrix material, in use can cause overlayer and matrix material local detachment, peel off, influence usability.So, how these thickness are only accounted for whole workpiece thickness more than one percent to 1/tens overlayers and carry out ultrasonic nonodestruction evaluation, be an important topic that must face.If utilize ultrasonic bulk wave, be difficult to thin layer like this is made effective ultrasonic nonodestruction evaluation.

Ultrasonic non-destructive inspection techniques all has a wide range of applications as one of obligato detection means in Modern Industry Products manufacturing and the use in all fields.The ultrasonic non-destructive inspection techniques of comparative maturity is primarily aimed at the defective initial sum accumulation stage and the ultimate failure stage of material or structure at present, like the existence and the distribution of defectives such as the micropore in the detecting material, micro-crack.Wherein mainly be applied to the information such as time-histories, the velocity of sound, decay, impedance, scattering of ripple.But these parameters are very insensitive to the degeneration of material and the early stage mechanical property of structure.

In recent years, the non-linear ultrasonic technology has caused people's extensive attention.Increasing research shows that the performance degradation that material damage causes and hyperacoustic nonlinear effect are closely related.But utilizing hyperacoustic nonlinear effect that Nondestructive Evaluation is carried out in coating damage also is not reported.Material damage will make wherein the ultrasound wave waveform of propagating produce distortion, cause having in the ultrasound wave of single-frequency the generation of high-frequency harmonic.Therefore through measurement Research, find its ultrasound non-linear coefficient that is in different phase, can make effective Non-Destructive Testing the degree of injury of coating to these high-frequency harmonics.For this reason, the present invention proposes a kind of non-linear ultrasonic Nondestructive Evaluation method of metal material coating damage.

Summary of the invention

The technical matters that the present invention will solve:

Propose a kind of non-linear ultrasonic Nondestructive Evaluation method of metal material coating damage, provide and confirm that coating lost efficacy and the foundation of judgement coating degree of injury.

The non-linear ultrasonic Nondestructive Evaluation method of the metal material coating damage that the present invention proposes, its ultimate principle is:

Auspicious Leibo is under the condition that velocity of propagation equates, to be formed by stacking with plane heterogeneous shear wave in plane heterogeneous compressional wave, therefore can the displacement of auspicious Leibo be decomposed into the vertical and horizontal displacement component, promptly ${\mathrm{\&mu;}}_x=B_1(e^{-\mathrm{Pz}}-\frac{2\mathrm{<figure-callout\; id="2"\; label="Ps\; k\; R"\; filenames="HDA0000157143580000011.png"\; state="\{\{state\}\}">Ps</figure-callout>}}{k_R^{}}{e}^{-\mathrm{Sz}})e^{i(k_{R}x-\mathrm{\&omega;\; t})},$ $u_z={\mathrm{IB}}_1\frac{p}{k_R}(e^{-\mathrm{Pz}}-\frac{{2k}_R^2}{{\mathrm{<figure-callout\; id="2"\; label="k\; R"\; filenames="HDA0000157143580000011.png"\; state="\{\{state\}\}">k</figure-callout>}}_R^{}+s^2}{e}^{-\mathrm{Sz}})e^{i(k_{R}x-\mathrm{\&omega;\; t})}$

In the material with weak quadratic nonlinearity, its second harmonic can approximate representation be after certain distance was propagated in auspicious Leibo:

$u_x\&ap;B_2(e^{-2\mathrm{pz}}-\frac{2\mathrm{<figure-callout\; id="2"\; label="ps\; k\; R"\; filenames="HDA0000157143580000011.png"\; state="\{\{state\}\}">ps</figure-callout>}}{k_R^{}}{e}^{-2\mathrm{sz}})e^{i2(k_{R}x-\mathrm{\&omega;t})},$ $u_z\&ap;i{B}_2\frac{p}{k_R}(e^{-2\mathrm{pz}}-\frac{{2k}_R^2}{{\mathrm{<figure-callout\; id="2"\; label="k\; R"\; filenames="HDA0000157143580000011.png"\; state="\{\{state\}\}">k</figure-callout>}}_R^{}+s^2}{e}^{-2\mathrm{sz}})e^{i2(k_{R}x-\mathrm{\&omega;t})}$

Concerning isotropic material, because the symmetry of its three rank elastic constant has only the auspicious Leibo of compressional wave and high-order relevant.Therefore near Free Surface, the relation in the auspicious Leibo between fundamental frequency displacement and the frequency multiplication displacement is consistent with the corresponding relation of compressional wave.So

$B_2=\frac{{\mathrm{\&beta;}}_R{k}_l^{2}x{B}_1^2}{8}$

β wherein _RBe the nonlinear factor of compressional wave composition in the auspicious Leibo, x is the propagation distance of auspicious Leibo.The displacement of Free Surface auspicious Leibo fundamental frequency and frequency multiplication is satisfied:

$\frac{u_z(2\mathrm{\&omega;};x,0)}{u_z^2(\mathrm{\&omega;};x,0)}\&ap;\frac{{\mathrm{\&beta;}}_R{k}_l^{2}x}{8i\frac{p}{k_R}(1-\frac{2k_R^2}{{\mathrm{<figure-callout\; id="2"\; label="k\; R"\; filenames="HDA0000157143580000011.png"\; state="\{\{state\}\}">k</figure-callout>}}_R^{}+s^2})}$

But the nonlinear factor by following formula De Ruilei surface wave is:

${\mathrm{\&beta;}}_R=\frac{u_z(2\mathrm{\&omega;};x,0)}{u_z^2(\mathrm{\&omega;};x,0)}\frac{8i}{k_l^{2}x}\frac{p}{k_R}(1-\frac{{2k}_R^2}{k_{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="HDA0000157143580000011.png"\; state="\{\{state\}\}">R</figure-callout>}}^2+s^2})$

Since in the ultrasonic experiment, the auspicious Leibo signal fundamental frequency amplitude A that receives ₁With frequency multiplication amplitude A ₂Be directly proportional with the frequency multiplication displacement with the fundamental frequency in the following formula, under the identical situation of propagation distance, nonlinear factor is just relevant with the displacement of fundamental frequency and frequency multiplication.Therefore the relative nonlinear coefficient that defines auspicious Leibo is:

${\mathrm{\&beta;}}_R=\frac{A_2}{A_1^2}$

Technical scheme of the present invention:

A kind of nonlinear ultrasonic evaluation method of metal material coating damage, it comprises following steps:

Step 1 is selected a coating test specimen, removes the lip-deep coating in coating test specimen two ends, and in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus and auspicious Leibo receiving trap respectively; Adopt the non-linear ultrasonic test macro to excite and receive auspicious Leibo signal; Through computer interface, utilize its initial auspicious Leibo signal of computer recording;

Step 2 prepares to have the coating test specimen of different degree of injury

Coating test specimen in the step 1 is carried out loading the first time, and pulling force is 6KN～8KN;

The coating test specimen is unloaded from charger, and in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus and auspicious Leibo receiving trap respectively;

Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, and the auspicious Leibo signal that utilizes computer recording to test for the first time;

Carry out loading the second time to loading for the first time the coating test specimen, pulling force is 14KN～16KN;

To load the coating test specimen for the second time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus and auspicious Leibo receiving trap respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, and the auspicious Leibo signal that utilizes computer recording to test for the second time;

Load for the third time loading the coating test specimen for the second time, pulling force is 22KN～24KN;

To load the coating test specimen for the third time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus and auspicious Leibo receiving trap respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, and the auspicious Leibo signal that utilizes computer recording to test for the third time;

Carry out the 4th loading to loading the coating test specimen for the third time, pulling force is 30KN～32KN;

Load the coating test specimen with the 4th time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus and auspicious Leibo receiving trap respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, and the auspicious Leibo signal that utilizes computer recording to test for the third time;

Load the coating test specimen to the 4th time and carry out the 5th loading, pulling force is 38KN～40KN, and this moment, crackle appearred in the electrodeposited coating part on test specimen surface;

Load the coating test specimen with the 5th time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus and auspicious Leibo receiving trap respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the auspicious Leibo signal of the 5th test of computer recording;

Step 3

Auspicious Leibo signal to first to the 5th time in the initial auspicious Leibo signal of step 1 and step 2 test adds Hanning window and carries out Fast Fourier Transform (FFT), obtains the fundamental frequency amplitude A in the auspicious Leibo signal of computer recording ₁With frequency multiplication amplitude A ₂

Definition relative nonlinear coefficient: β _R=A ₂/ A ₁ ²

The prima facies of initial auspicious Leibo signal in the step 1 is designated as β to nonlinear factor _R0

With the prima facies of step 1 China and Sweden Leibo signal to nonlinear factor divided by β _R0Carry out regularization, obtain the initial regularization relative nonlinear coefficient value of coating test specimen;

With the relative nonlinear coefficient of the auspicious Leibo signal of test for the first time divided by β _R0Carry out regularization, first regularization relative nonlinear coefficient value after obtaining the coating test specimen and loading for the first time;

With the relative nonlinear coefficient of the auspicious Leibo signal of test for the second time divided by β _R0Carry out regularization, second regularization relative nonlinear coefficient value after obtaining the coating test specimen and loading for the second time;

With the relative nonlinear coefficient of auspicious Leibo signal of test for the third time divided by β _R0Carry out regularization, the 3rd regularization relative nonlinear coefficient value after obtaining the coating test specimen and loading for the third time;

With the relative nonlinear coefficient of auspicious Leibo signal of the 4th test divided by β _R0Carry out regularization, obtain the 4th regularization relative nonlinear coefficient value after the coating test specimen loads for the 4th time;

With the relative nonlinear coefficient of auspicious Leibo signal of the 5th test divided by β _R0Carry out regularization, obtain the 5th regularization relative nonlinear coefficient value after the coating test specimen loads for the 5th time;

With the cross-sectional area of the pulling force that loads in the step 2 divided by the coating test specimen at every turn, the stress that obtains five loadings is represented;

With regularization relative nonlinear coefficient is ordinate; With stress is horizontal ordinate; Initial regularization relative nonlinear coefficient value with step 1 China and Sweden Leibo signal; And above-mentioned five regularization relative nonlinear coefficient values are illustrated in the above-mentioned coordinate, obtain the graph of relation between regularization relative nonlinear coefficient and stress;

The non-linear ultrasonic evaluation of step 4 metal material coating damage

According to the graph of relation between regularization relative nonlinear coefficient and stress, when the relative nonlinear coefficient greater than 1 and during regularization relative nonlinear coefficient value when crackle occurring less than coating, there is damage in the coating test specimen; The relative nonlinear coefficient is big more, and degree of injury is big more.

The beneficial effect of the invention is:

Generation catastrophic failure in back causes a large amount of industrial crucial coating parts generation sudden accidents owing to the damage of metal bearing carrier runs up to a certain degree.Therefore, propose a kind of effective Dynamic Non-Destruction Measurement, a large amount of coating component damage degree of using in fields such as present Aeronautics and Astronautics, the energy, petrochemical industry are realized detecting, this is to guaranteeing industrial security of operation and being avoided great interruption of service significant.

Description of drawings

Fig. 1 is a non-linear ultrasonic test macro synoptic diagram.

Fig. 2 is the graph of relation between regularization relative nonlinear coefficient and stress.

Among the figure: oscillograph 1, main frame 2, computing machine 3, preposition decay and low-pass filtering module 4, auspicious Leibo excitation apparatus 5, coating test specimen 6, auspicious Leibo receiving trap 7, high-pass filtering module 8.

Embodiment

Below in conjunction with accompanying drawing and embodiment, the present invention is described in further detail.

The non-linear ultrasonic test macro, as shown in Figure 1, it comprises: oscillograph 1, main frame 2, computing machine 3, preposition decay and low-pass filtering module 4, auspicious Leibo excitation apparatus 5, auspicious Leibo receiving trap 7, high-pass filtering module 8.The model of oscillograph 1 is TDS3034B, and the model of main frame 2 is Ritec SNAP-0.25-7-G2, and the model of preposition decay and low-pass filtering module 4 is RLP-2, and the model of high-pass filtering module 8 is RHP-4.Utilize concentric cable that the signal output part A of main frame 2 is connected with the input end of preposition decay and low-pass filtering module 4; The output terminal of preposition decay and low-pass filtering module 4 is connected with auspicious Leibo excitation apparatus 5; One road signal of auspicious Leibo receiving trap 7 devices inserts high-pass filtering module 8 input ends; The output terminal of high-pass filtering module 8 is connected with the receiving end B of main frame 2, and another road signal of auspicious Leibo receiving trap 7 inserts the receiving end C of main frame 2, and the signal monitoring port D of main frame 2 is connected with oscillograph 1.

A kind of nonlinear ultrasonic evaluation method one of metal material coating damage may further comprise the steps:

Step 1 is selected a coating test specimen 6, removes the lip-deep coating in coating test specimen two ends, and in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Adopt the non-linear ultrasonic test macro to excite and receive auspicious Leibo signal; Through computer interface, utilize computing machine 3 its initial auspicious Leibo signals of record;

Step 2 prepares to have the coating test specimen of different degree of injury

Coating test specimen in the step 1 is carried out loading the first time, and pulling force is 8KN;

The coating test specimen is unloaded from charger, and in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively;

Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the computing machine 3 records auspicious Leibo signal of test for the first time;

Carry out loading the second time to loading for the first time the coating test specimen, pulling force is 16KN;

To load the coating test specimen for the second time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the computing machine 3 records auspicious Leibo signal of test for the second time;

Load for the third time loading the coating test specimen for the second time, pulling force is 24KN;

To load the coating test specimen for the third time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the computing machine 3 records auspicious Leibo signal of test for the third time;

Carry out the 4th loading to loading the coating test specimen for the third time, pulling force is 32KN;

Load the coating test specimen with the 4th time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the computing machine 3 records auspicious Leibo signal of test for the third time;

Load the coating test specimen to the 4th time and carry out the 5th loading, pulling force is 40KN, and this moment, crackle appearred in the electrodeposited coating part on test specimen surface;

Load the coating test specimen with the 5th time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the auspicious Leibo signal of the 5th test of computing machine 3 records;

Step 3

Auspicious Leibo signal to first to the 5th test in the initial auspicious Leibo signal of step 1 and the step 2 adds Hanning window and carries out Fast Fourier Transform (FFT), obtains the fundamental frequency amplitude A in the auspicious Leibo signal of computer recording ₁With frequency multiplication amplitude A ₂

Definition relative nonlinear coefficient: β _R=A ₂/ A ₁ ²

The prima facies of initial auspicious Leibo signal in the step 1 is designated as β to nonlinear factor _R0

With the prima facies of step 1 China and Sweden Leibo signal to nonlinear factor divided by β _R0Carry out regularization, obtain the initial regularization relative nonlinear coefficient value 1 of coating;

With the relative nonlinear coefficient of the auspicious Leibo signal of test for the first time divided by β _R0Carry out regularization, first regularization relative nonlinear coefficient 1.291 after obtaining the coating test specimen and loading for the first time;

With the relative nonlinear coefficient of the auspicious Leibo signal of test for the second time divided by β _R0Carry out regularization, second regularization relative nonlinear coefficient 1.864 after obtaining the coating test specimen and loading for the second time;

With the relative nonlinear coefficient of auspicious Leibo signal of test for the third time divided by β _R0Carry out regularization, the 3rd regularization relative nonlinear coefficient 1.897 after obtaining the coating test specimen and loading for the third time;

With the relative nonlinear coefficient of auspicious Leibo signal of the 4th test divided by β _R0Carry out regularization, obtain the 4th regularization relative nonlinear coefficient 2.329 after the coating test specimen loads for the 4th time;

With the relative nonlinear coefficient of auspicious Leibo signal of the 5th test divided by β _R0Carry out regularization, obtain the 5th regularization relative nonlinear coefficient 2.642 after the coating test specimen loads for the 5th time;

With the cross-sectional area 312mm of the pulling force that loads in the step 2 at every turn divided by the coating test specimen ², the stress that obtains five loadings representes to be respectively 25.6MPa, 51.3MPa, 76.9MPa, 102.5MPa, 128.2MPa;

With regularization relative nonlinear coefficient is ordinate; With stress is horizontal ordinate; Initial regularization relative nonlinear coefficient value with step 1 China and Sweden Leibo signal; And above-mentioned five regularization relative nonlinear coefficient values are illustrated in the above-mentioned coordinate, obtain the graph of relation between regularization relative nonlinear coefficient and stress, and are as shown in Figure 2;

The non-linear ultrasonic evaluation of step 4 metal material coating damage

According to the loading observation of coating test specimen and the measurement of nonlinear factor, be 2.642 o'clock at regularization relative nonlinear coefficient, the coating test specimen crackle occurs and lost efficacy; According to the graph of relation between regularization relative nonlinear coefficient and stress, when the relative nonlinear coefficient greater than 1 and less than 2.642 the time, there is damage in the coating test specimen, the relative nonlinear coefficient is big more, degree of injury is big more.

A kind of nonlinear ultrasonic evaluation method two of metal material coating damage may further comprise the steps:

Step 1 is selected a coating test specimen 6, removes the lip-deep coating in coating test specimen two ends, and in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Adopt the non-linear ultrasonic test macro to excite and receive auspicious Leibo signal; Through computer interface, utilize computing machine 3 its auspicious Leibo signals of record;

Step 2 prepares to have the coating test specimen of different degree of injury

Coating test specimen in the step 1 is carried out loading the first time, and pulling force is 6KN;

The coating test specimen is unloaded from charger, and in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively;

Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the computing machine 3 records auspicious Leibo signal of test for the first time;

Carry out loading the second time to loading for the first time the coating test specimen, pulling force is 14KN;

To load the coating test specimen for the second time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the computing machine 3 records auspicious Leibo signal of test for the second time;

Load for the third time loading the coating test specimen for the second time, pulling force is 22KN;

To load the coating test specimen for the third time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the computing machine 3 records auspicious Leibo signal of test for the third time;

Carry out the 4th loading to loading the coating test specimen for the third time, pulling force is 30KN;

Load the coating test specimen with the 4th time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the computing machine 3 records auspicious Leibo signal of test for the third time;

Load the coating test specimen to the 4th time and carry out the 5th loading, pulling force is 38KN;

Load the coating test specimen with the 5th time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus 5 and auspicious Leibo receiving trap 7 respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the auspicious Leibo signal of the 5th test of computing machine 3 records;

Step 3

Auspicious Leibo signal to first to the 5th test in the initial auspicious Leibo signal of step 1 and the step 2 adds Hanning window and carries out Fast Fourier Transform (FFT), obtains the fundamental frequency amplitude A in the auspicious Leibo signal of computer recording ₁With frequency multiplication amplitude A ₂

Definition relative nonlinear coefficient: β _R=A ₂/ A ₁ ²

The prima facies of initial auspicious Leibo signal in the step 1 is designated as β to nonlinear factor _R0

With the prima facies of step 1 China and Sweden Leibo signal to nonlinear factor divided by β _R0Carry out regularization, obtain the initial regularization relative nonlinear coefficient value 1 of coating test specimen;

With the relative nonlinear coefficient of the auspicious Leibo signal of test for the first time divided by β _R0Carry out regularization, first regularization relative nonlinear coefficient 1.241 after obtaining the coating test specimen and loading for the first time;

With the relative nonlinear coefficient of the auspicious Leibo signal of test for the second time divided by β _R0Carry out regularization, second regularization relative nonlinear coefficient 1.753 after obtaining the coating test specimen and loading for the second time;

With the relative nonlinear coefficient of auspicious Leibo signal of test for the third time divided by β _R0Carry out regularization, the 3rd regularization relative nonlinear coefficient 1.957 after obtaining the coating test specimen and loading for the third time;

With the relative nonlinear coefficient of auspicious Leibo signal of the 4th test divided by β _R0Carry out regularization, obtain the 4th regularization relative nonlinear coefficient 2.225 after the coating test specimen loads for the 4th time;

With the relative nonlinear coefficient of auspicious Leibo signal of the 5th test divided by β _R0Carry out regularization, obtain the 5th regularization relative nonlinear coefficient 2.519 after the coating test specimen loads for the 5th time;

With the cross-sectional area 312mm of the pulling force that loads in the step 2 at every turn divided by the coating test specimen ², the stress that obtains five loadings representes to be respectively 19.2MPa, 44.9MPa, 70.5MPa, 96.2MPa, 121.8MPa;

With regularization relative nonlinear coefficient is ordinate; With stress is horizontal ordinate; Initial regularization relative nonlinear coefficient value with step 1 China and Sweden Leibo signal; And above-mentioned five regularization relative nonlinear coefficient values are illustrated in the above-mentioned coordinate, obtain the graph of relation between regularization relative nonlinear coefficient and stress, and are as shown in Figure 2;

The non-linear ultrasonic evaluation of step 4 metal material coating damage

According to the graph of relation between regularization relative nonlinear coefficient and stress, when the relative nonlinear coefficient greater than 1 and less than 2.519 the time, there is damage in the coating test specimen; The relative nonlinear coefficient is big more, and degree of injury is big more.

Claims (1)

1. the nonlinear ultrasonic evaluation method of a metal material coating damage is characterized in that, comprises following steps:

Step 1 is selected a coating test specimen, removes the lip-deep coating in coating test specimen two ends, and in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus (5) and auspicious Leibo receiving trap (7) respectively; Adopt the non-linear ultrasonic test macro to excite and receive auspicious Leibo signal; Through computer interface, utilize computing machine (3) to write down its initial auspicious Leibo signal;

Step 2 prepares to have the coating test specimen of different degree of injury

Coating test specimen in the step 1 is carried out loading the first time, and pulling force is 6KN～8KN;

The coating test specimen is unloaded from charger, and in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus (5) and auspicious Leibo receiving trap (7) respectively;

Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes computing machine (3) the record auspicious Leibo signal of test for the first time;

Carry out loading the second time to loading for the first time the coating test specimen, pulling force is 14KN～16KN;

To load the coating test specimen for the second time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus (5) and auspicious Leibo receiving trap (7) respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes computing machine (3) the record auspicious Leibo signal of test for the second time;

Load for the third time loading the coating test specimen for the second time, pulling force is 22KN～24KN;

To load the coating test specimen for the third time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus (5) and auspicious Leibo receiving trap (7) respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes computing machine (3) the record auspicious Leibo signal of test for the third time;

Carry out the 4th loading to loading the coating test specimen for the third time, pulling force is 30KN～32KN;

Load the coating test specimen with the 4th time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus (5) and auspicious Leibo receiving trap (7) respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes computing machine (3) the record auspicious Leibo signal of test for the third time;

Load the coating test specimen to the 4th time and carry out the 5th loading, pulling force is 38KN～40KN, and this moment, crackle appearred in the electrodeposited coating part on test specimen surface;

Load the coating test specimen with the 5th time and unload from charger, in the position that coating test specimen two end surfaces are removed coating, next-door neighbour's coating is placed auspicious Leibo excitation apparatus (5) and auspicious Leibo receiving trap (7) respectively; Employing non-linear ultrasonic test macro excites and receives auspicious Leibo signal, through computer interface, utilizes the auspicious Leibo signal of the 5th test of computing machine (3) record;

Step 3

Auspicious Leibo signal to first to the 5th time in the initial auspicious Leibo signal of step 1 and step 2 test adds Hanning window and carries out Fast Fourier Transform (FFT), obtains the fundamental frequency amplitude A in the auspicious Leibo signal of computer recording ₁With frequency multiplication amplitude A ₂

Definition relative nonlinear coefficient: β _R=A ₂/ A ₁ ²

The prima facies of initial auspicious Leibo signal in the step 1 is designated as β to nonlinear factor _R0

With the prima facies of step 1 China and Sweden Leibo signal to nonlinear factor divided by β _R0Carry out regularization, obtain the initial regularization relative nonlinear coefficient value of coating test specimen;

With the relative nonlinear coefficient of the auspicious Leibo signal of test for the first time divided by β _R0Carry out regularization, first regularization relative nonlinear coefficient value after obtaining the coating test specimen and loading for the first time;

With the relative nonlinear coefficient of the auspicious Leibo signal of test for the second time divided by β _R0Carry out regularization, second regularization relative nonlinear coefficient value after obtaining the coating test specimen and loading for the second time;

With the relative nonlinear coefficient of auspicious Leibo signal of test for the third time divided by β _R0Carry out regularization, the 3rd regularization relative nonlinear coefficient value after obtaining the coating test specimen and loading for the third time;

With the relative nonlinear coefficient of auspicious Leibo signal of the 4th test divided by β _R0Carry out regularization, obtain the 4th regularization relative nonlinear coefficient value after the coating test specimen loads for the 4th time;

With the relative nonlinear coefficient of auspicious Leibo signal of the 5th test divided by β _R0Carry out regularization, obtain the 5th regularization relative nonlinear coefficient value after the coating test specimen loads for the 5th time;

With the cross-sectional area of the pulling force that loads in the step 2 divided by the coating test specimen at every turn, the stress that obtains five loadings is represented;

With regularization relative nonlinear coefficient is ordinate; With stress is horizontal ordinate; Initial regularization relative nonlinear coefficient value with step 1 China and Sweden Leibo signal; And above-mentioned five regularization relative nonlinear coefficient values are illustrated in the above-mentioned coordinate, obtain the graph of relation between regularization relative nonlinear coefficient and stress;

The non-linear ultrasonic evaluation of step 4 metal material coating damage

According to the graph of relation between regularization relative nonlinear coefficient and stress, when the relative nonlinear coefficient greater than 1 and during regularization relative nonlinear coefficient value when crackle occurring less than coating, there is damage in the coating test specimen; The relative nonlinear coefficient is big more, and degree of injury is big more.

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