Model for measuring thickness of dissimilar material composite board based on correction ultrasound

Abstract

The invention discloses a model for measuring the thickness of a dissimilar material composite board based on correction ultrasound. The method comprises the following steps: acquiring the total propagation time of ultrasonic waves in different materials of the composite board based on different propagation speeds of the ultrasonic waves in different materials, acquiring the total test thickness of the composite board in other modes, and establishing a thickness-propagation time model according to the total propagation time of the ultrasonic waves in the test bimetal composite board and the total test thickness, obtaining a finished product. According to the model, mechanical testing and ultrasonic testing are combined, an ultrasonic thickness measuring result is corrected by testing the real total thickness of the composite board, the testing precision of the thickness of each layer of the composite board can be greatly improved, the testing efficiency can be greatly improved, rapid and accurate testing is achieved, and further, the testing efficiency is improved. The model can also realize accurate testing of the thickness of each layer of the all-material composite board, and the application range of the model is greatly expanded.

Description

Technical Field

[0001] The invention discloses a composite plate thickness model, in particular to a model for measuring the thickness of a composite plate made of different materials based on calibrated ultrasound, and belongs to the technical field of metal material thickness measurement. Background Art

[0002] With the development of industrial refinement, more and more industries have begun to use layered metal composite materials. Layered metal composite materials are generally composed of substrates and covering materials. Usually, the substrate acts as the bones and exerts the role of structural force, while the covering material acts as the skin, which is in direct contact with the medium and plays a role in corrosion resistance. For the connection of special dissimilar metals, layered metal composite materials can also act as bridges and ties, so that dissimilar metals that are difficult to weld can be conveniently welded metallurgically through dissimilar metal transition joints. The preparation of layered metal composite materials usually includes: rolling composite, explosive composite, friction composite, diffusion composite and other methods. The thickness of the base coating of layered metal composite materials is a key parameter, which has a great influence on the corrosion resistance, service life and carrying current of layered metal composite materials. How to quickly and accurately measure the thickness of the base coating of bimetallic composite plates is a difficult problem in actual production.

[0003] Commonly used thickness measurement methods for bimetallic composite plates include vernier caliper thickness measurement, magnetic thickness measurement, metallographic thickness measurement and ultrasonic thickness measurement. When using a vernier caliper to measure the thickness of the base coating layer of the cross-section of the composite plate sample, it is necessary to visually distinguish the base coating boundary line. This measurement is highly subjective and the measured value is relatively rough. The magnetic method thickness measurement uses the principle of magnetic induction to measure the thickness of the non-magnetic coating on the magnetic substrate. It is suitable for measuring titanium-steel and copper-steel composite plates with ferromagnetic substrates and non-magnetic coatings. It cannot measure non-magnetic copper-aluminum composite plates. The metallographic method thickness measurement has the characteristics of strong versatility and high measurement accuracy, but the measurement process is cumbersome and the real-time performance is poor. It is necessary to cut, sample, grind, and polish the test composite plate, and it is difficult to perform non-destructive testing on the target composite plate. The ultrasonic method thickness measurement is based on the difference in acoustic impedance of the two materials, which causes the ultrasonic wave to reflect at the composite interface. The instrument measures the base coating thickness by capturing the interface reflection wave. It has the advantages of convenient operation and good real-time performance. However, for the two metal interfaces with smaller acoustic impedance, the reflection wave is small, and it is difficult to accurately capture and measure. For example, in the measurement of stainless steel-steel composite plates, it is difficult to effectively calculate the thickness of each layer of the composite plate.

[0004] Therefore, the existing market urgently needs to provide a convenient and practical thickness measurement method. Summary of the invention

[0005] In view of the problems existing in the prior art, the purpose of the present invention is to provide a model for measuring the thickness of heterogeneous composite plates based on calibrated ultrasound. The model combines mechanical testing with ultrasonic testing, and uses the actual total thickness of the tested composite plate to calibrate the ultrasonic thickness measurement results. This can not only greatly improve the test accuracy of the thickness of each layer of the composite plate, but also greatly improve the test rate, and achieve fast and accurate testing. Furthermore, the model can also achieve accurate testing of the thickness of each layer of the full-material composite plate, greatly expanding the scope of application of the model.

[0006] In order to achieve the above technical purpose, the present invention provides a model for measuring the thickness of a composite plate of heterogeneous materials based on calibrated ultrasound, step S1, obtaining the propagation speed of ultrasound in different materials of the composite plate;

[0007] Step S2, obtaining the actual total thickness of the composite plate, and then obtaining the total tested thickness of the composite plate by an ultrasonic thickness gauge;

[0008] Step S3, establishing a thickness-propagation velocity model according to the propagation velocity obtained in step S1 and the actual total thickness and the tested total thickness obtained in step S2, to obtain.

[0009] As a preferred solution, the composite plate is composed of a covering material and a substrate, and the material of the covering material is an ultrasonically stable material.

[0010] As a preferred solution, the material of the composite plate is any two of an inorganic non-metallic material, an organic non-metallic material and a metallic material.

[0011] As a preferred solution, the composite plate is any one of titanium-steel alloy, copper-steel alloy, copper-aluminum alloy, carbon fiber-aluminum composite material and carbon fiber-steel composite material.

[0012] As a preferred solution, the true total thickness is tested by any one of mechanical thickness measurement, metallographic thickness measurement and magnetic thickness measurement.

[0013] As a preferred solution, the thickness-test time model is established as follows:

[0014] Step S3-1, establishing a correlation equation between the thickness of the covering material, the thickness of the substrate and the actual thickness of the composite board;

[0015] Step S3-2, according to the propagation speed of ultrasound in different materials of the composite board, establish a correlation equation between the propagation time of ultrasound in the covering material, the propagation time in the substrate, and the propagation time in the total thickness of the composite board test;

[0016] Step S3-3, combine the correlation equations obtained in step S3-1 and step S3-2 to obtain.

[0017] As a preferred solution, the calculation process of the thickness-test time model is:

[0018] Formula 1: a+b=δ 1 ;

[0019] Formula 2:

[0020] Formula 3:

[0021] Formula 4:

[0022] In formulas 1 to 4: a is the thickness of the covering material, b is the thickness of the substrate, c is 1 is the propagation speed of ultrasonic wave in the covering material, c 2 is the propagation speed of ultrasonic waves in the substrate, c 超 is any given propagation velocity when ultrasonic testing the total thickness of the composite plate, δ 1 is the actual total thickness of the composite plate, δ 超 It is the total thickness of the composite plate tested according to a given propagation velocity.

[0023] As a preferred solution, the δ 1 Obtained by vernier caliper, δ 超 Measured by ultrasonic tester, c 1 、c 2 Obtained by ultrasonic tester calibration measurement or table lookup, c 超 To input any given value of the ultrasonic detector.

[0024] Compared with the prior art, the beneficial technical effects of the technical solution of the present invention are:

[0025] 1) The model provided by the present invention combines mechanical testing with ultrasonic testing, and uses the actual total thickness of the tested composite plate to correct the ultrasonic thickness measurement result. This can not only greatly improve the test accuracy of the thickness of each layer of the composite plate, but also greatly improve the test rate, and achieve fast and accurate testing. Furthermore, the model can also realize accurate testing of the thickness of each layer of the full-material composite plate, greatly expanding the scope of application of the model.

[0026] 2) The technical solution provided by the present invention is based on the true total thickness and the total thickness tested by ultrasonic wave. There is no need to visually distinguish the boundary line between the substrate and the cladding material, so it has high objectivity and more accurate test results. Moreover, due to the introduction of the true total thickness of mechanical testing, the application scope of ultrasonic thickness measurement is greatly expanded, and the technical problem that the existing ultrasonic thickness measurement method cannot accurately measure non-magnetic copper-aluminum composite plates and composite plates with small ultrasonic impedance is effectively overcome. After testing, the test error of the model is less than 50μm, which has excellent accuracy and speed. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative ideas are within the scope of protection of the present invention.

[0028] Example 1

[0029] This embodiment provides a model for measuring the thickness of a composite plate of heterogeneous materials based on calibrated ultrasound. The specific modeling process is as follows:

[0030] 1) Establish the correlation equation between the thickness of the covering material, the thickness of the substrate and the true thickness of the composite plate;

[0031] Formula 1: a+b=δ 1 ;

[0032] 2) According to the propagation speed of ultrasound in different materials of the composite plate, establish the correlation equation between the propagation time of ultrasound in the covering material, the propagation time in the substrate and the propagation time in the total thickness of the composite plate test;

[0033] Formula 2:

[0034] 3) Combining equation 1 and equation 2, we get:

[0035] Formula 3:

[0036] Formula 4:

[0037] In formulas 1 to 4: a is the thickness of the covering material, b is the thickness of the substrate, c is 1 is the propagation speed of ultrasonic wave in the covering material, c 2 is the propagation speed of ultrasonic waves in the substrate, c 超 is any given propagation velocity when ultrasonic testing the total thickness of the composite plate, δ 1 is the actual total thickness of the composite plate, δ 超 It is the total thickness of the composite plate tested according to a given propagation velocity.

[0038] The above model was used to measure the thickness of the cladding material of 304 stainless steel and the base material of Q345R steel: the total thickness δ was measured with a vernier caliper 1 is 34.56 mm, and the ultrasonic thickness gauge sound velocity c is arbitrarily input 超 =5900m / s, the total thickness of the composite plate is measured 超 =34.69, according to the table, the propagation speed of longitudinal waves in stainless steel c 1 =5740m / s, the propagation speed of sound of the base carbon steel c2 =5900m / s, the thickness of the coating is calculated to be a = 4.86mm, and the thickness of the substrate is b = 29.7mm. The thickness of the coating is 4.836mm and the thickness of the substrate is 29.736mm by metallographic microscopic measurement. The relative error is within 0.1mm, which meets the daily production error requirements.

[0039] Example 2

[0040] The above model was used to measure the thickness of the cladding material 1060 pure aluminum and the substrate T2 pure copper, and the total thickness δ was measured with a vernier caliper. 1 is 72.22 mm, and the arbitrarily input sound velocity of the ultrasonic thickness gauge is c 超 =5900m / s, the instrument measures the thickness of the composite plate δ 超 =80.37mm, according to the table, the propagation speed of longitudinal wave in pure aluminum 1060 is c 1 =6300m / s, the propagation speed of sound c of the base material pure aluminum 1060 2 =4700m / s, the thickness of the cladding material 1060 is calculated to be a=32.26mm, and the thickness of the substrate pure copper T2 is b=39.96mm. By comparison, the thickness of the cladding material pure aluminum 1060 is 32.303mm, and the thickness of the substrate is 39.924mm. The relative error is within 0.1mm, which meets the daily production error requirements.

[0041] Example 3

[0042] The above model was used to measure the thickness of the Q235B steel plate with resin as the cladding material and Q235B steel plate as the substrate, and the total thickness δ was measured with a vernier caliper. 1 is 50.16 mm, and the arbitrarily input sound velocity of the ultrasonic thickness gauge is c 超 =5900m / s, the instrument measures the thickness of the composite plate δ 超 =61.30mm, according to the table, the propagation speed of longitudinal wave in resin c 1 =2760m / s, the propagation speed of sound c of the base material Q235B 2 =5900m / s, the thickness of the coating resin is calculated to be a=10.12mm, and the thickness of the base material pure Q235B is b=39.67mm. By comparison, the thickness of the coating resin measured by metallographic microscopy is 10.162mm, and the thickness of the base material is 39.622mm. The relative error is within 0.1mm, which meets the daily production error requirements.

Claims

1. A model for measuring the thickness of heterogeneous composite plates based on calibrated ultrasound, characterized in that: include: Step S1, obtaining the propagation speed of ultrasonic waves in different materials of the composite plate; Step S2, obtaining the actual total thickness of the composite plate, and then obtaining the total tested thickness of the composite plate by an ultrasonic thickness gauge; Step S3, establishing a thickness-propagation velocity model according to the propagation velocity obtained in step S1 and the actual total thickness and the tested total thickness obtained in step S2, to obtain.

2. A model for measuring the thickness of a composite plate of heterogeneous materials based on calibrated ultrasound according to claim 1, characterized in that: The composite plate is composed of a covering material and a base material, and the material thereof is an ultrasonically stable material.

3. A model for measuring the thickness of a composite plate of heterogeneous materials based on calibrated ultrasound according to claim 2, characterized in that: The material of the composite plate is any two of inorganic non-metallic materials, organic non-metallic materials and metallic materials.

4. A model for measuring the thickness of a composite plate of heterogeneous materials based on calibrated ultrasound according to claim 3, characterized in that: The composite plate is any one of titanium-steel alloy, copper-steel alloy, copper-aluminum alloy, carbon fiber-aluminum composite material and carbon fiber-steel composite material.

5. The model for measuring the thickness of heterogeneous composite plates based on calibrated ultrasound according to claim 3 is characterized by: The actual total thickness is measured by any one of mechanical thickness measurement, metallographic thickness measurement and magnetic thickness measurement.

6. A model for measuring the thickness of a composite plate of heterogeneous materials based on calibrated ultrasound according to claim 3, characterized in that: The establishment process of the thickness-test time model is: Step S3-1, establishing a correlation equation between the thickness of the covering material, the thickness of the substrate and the actual thickness of the composite board; Step S3-2, according to the propagation speed of ultrasound in different materials of the composite board, establish a correlation equation between the propagation time of ultrasound in the covering material, the propagation time in the substrate, and the propagation time in the total thickness of the composite board test; Step S3-3, combine the correlation equations obtained in step S3-1 and step S3-2 to obtain.

7. A model for measuring the thickness of a composite plate of heterogeneous materials based on calibrated ultrasound according to claim 6, characterized in that: The calculation process of the thickness-test time model is: Formula 1: a+b=δ1; Formula 2: Formula 3: Formula 4: In formulas 1 to 4, a is the thickness of the covering material, b is the thickness of the substrate, c1 is the propagation speed of the ultrasonic wave in the covering material, c2 is the propagation speed of the ultrasonic wave in the substrate, cchaode is an arbitrarily given propagation speed when ultrasonically testing the total thickness of the composite plate, δ1 is the actual total thickness of the composite plate, and δchaode is the total test thickness of the composite plate obtained by testing at a given propagation speed.

8. A model for measuring the thickness of a composite plate of heterogeneous materials based on calibrated ultrasound according to claim 7, characterized in that: The δ1 is obtained by a vernier caliper, δsuper is measured by an ultrasonic tester, c1 and c2 are obtained by calibration measurement of the ultrasonic tester or by table lookup, and csuper is an arbitrary given value input to the ultrasonic tester.

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