Probe for detecting corrosion and thinning defects of metal components and its quantitative evaluation method

Abstract

The present invention discloses a metal component corrosion and thinning defect detection probe and a quantitative assessment method. The probe comprises a matrix-arranged array of cube-shaped transparent sealed cabins and a matrix-arranged array of square coils. Each sealed cabin is filled with a white solution and a plurality of hollow plastic spheres uniformly sprayed with black magnetic powder. There is a square coil at the center bottom of each sealed cabin. The hollow plastic spheres have consistent geometric dimensions. The present invention also provides a detection method for the above-mentioned probe, which can perform rapid and high-precision detection of corrosion and thinning of in-service metal components and has important engineering application value.

Description

Technical Field

[0001] The invention belongs to the technical field of nondestructive testing and relates to a metal component defect detection probe and a quantitative evaluation method. Background Art

[0002] Due to complex service environments such as high temperature differences and humidity, metal components are prone to corrosion defects during service, which in turn reduces the service life of the metal components and seriously affects the safe operation of equipment. Therefore, high-precision and rapid detection of corrosion defects in metal components is of great significance. Currently, eddy current testing and pulsed eddy current testing are mostly used to detect corrosion defects in metal components. However, their detection efficiency is relatively low. There is still a gap in the research and engineering application of using new detection sensors for rapid detection of corrosion defects. Summary of the Invention

[0003] In order to solve the problems existing in the above-mentioned prior art, the purpose of the present invention is to propose a metal component corrosion thinning defect detection probe and quantitative evaluation method, which can perform rapid and high-precision quantitative evaluation of metal component corrosion defects and has important engineering application value.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The metal component corrosion and thinning defect detection probe includes a matrix-arranged cube transparent sealed cabin array 1, a matrix-arranged square coil array 4, a white solution 3 and a hollow plastic sphere 2 in the cube transparent sealed cabin array 1; the square coil array 4 is fixed at the center of the bottom surface of the cube transparent sealed cabin array 1, and one square coil is fixed to the bottom of each cube sealed cabin.

[0006] The cube transparent sealed cabin arrays 1 are made of transparent material, are tightly attached to each other and have their bottom surfaces in the same plane; the four sides of the square coil array are parallel to the corresponding sides of the cube transparent sealed cabin arrays 1.

[0007] A method for quantitatively evaluating corrosion thinning defects using a metal component corrosion thinning defect detection probe, comprising establishing a metal component corrosion thinning defect calibration curve and quantitatively evaluating the metal component corrosion thinning defects;

[0008] (1) Establishment of the calibration curve of corrosion thinning defects of metal components. The specific method is as follows:

[0009] Connect the signal generator, power amplifier and the square coil array 4 of the detection probe in sequence to form a detection system; a period of T , duty cycle is 50%, amplitude is I The detection probes are closely attached to the thickness ofd , 0.9 d , 0.8 d , 0.7 d , 0.6 d , 0.5 d , 0.4 d , 0.3 d , 0.2 d and 0.1 d On the surface of the metal component, since the detection probe will generate different intensities of induced eddy current fields in metal components of different thicknesses, the secondary magnetic fields caused by the induced eddy currents are different, and the total magnetic field strength is also different, the hollow plastic balls 2 corresponding to metal components of different thicknesses are subjected to different downward magnetic forces; at any moment, the hollow plastic balls 2 corresponding to metal components of different thicknesses are at different heights in the cube transparent sealed cabin array 1. When the camera is used to obtain its image, it is reflected in the grayscale images of the images corresponding to metal components of different thicknesses. A camera with a lens surface parallel to the surface of the cube transparent sealed cabin array 1 is fixed above the center of the cube transparent sealed cabin array 1. L 0 and the excitation current is 0.5 T Take pictures at the same time to obtain the grayscale images of 10 metal components in the area of the cube transparent sealed cabin array 1. G 1. G 2. G 3. G 4. G 5. G 6. G 7. G 8. G 9 and G 10 , and calculate the average grayscale value of all pixels in the grayscale image g 1. g 2. g 3. g 4. g 5. g 6. g 7. g 8. g 9 and g 10 ;by g 1. g 2. g 3. g 4. g 5. g 6. g 7. g 8. g 9 and g 10 As the horizontal axis, 0, 0.1 d , 0.2 d , 0.3d , 0.4 d , 0.5 d , 0.6 d , 0.7 d , 0.8 d and 0.9 d As the vertical coordinate, the depth of corrosion thinning defects of metal components is obtained d n and the average gray value g The correlation curve is fitted by quadratic fitting to obtain the fitting formula d n = ag 2 + bg + c ,in a 、 b 、 c are constants respectively;

[0010] (2) Quantitative evaluation of corrosion thinning defects of metal components. The specific methods are as follows:

[0011] The signal generator, power amplifier and the square coil array 4 of the detection probe are connected in sequence, and a period of T , duty cycle is 50%, amplitude is I The detection probe is tightly attached to the surface of the metal component to be tested, and the camera with the lens surface parallel to the surface of the cube transparent sealed cabin array 1 is fixed above the center of the cube transparent sealed cabin array. L 0 and the excitation current is 0.5 T Take pictures at the same time and calculate the average gray value of each sealed cabin area in the cube transparent sealed cabin array 1 g 1，1 、 g 1，2 、 g 1，3 、 g 1，4 、 g 1，5 … g h，j ,in h and j are the rows and columns of the sealed cabin array respectively. The average gray value corresponding to any sealed cabin g i，k Substitute into the formula d n = ag 2 + bg + c The depth of corrosion thinning defects of metal components at any sealed cabin location can be obtained di，k ,Depend on d 1，1 、 d 1，2 、 d 1，3 、 d 1，4 、 d 1，5 … d h，j A two-dimensional distribution map of the depth of corrosion and thinning defects of metal components at position 1 of the cube transparent sealed cabin array can be obtained.

[0012] Compared with the prior art, the present invention has the following advantages:

[0013] 1. The probe of the present invention directly converts magnetic field signals into image grayscale signals, which can achieve rapid response to corrosion and thinning defects of metal components. Compared with traditional electromagnetic non-destructive testing technology, the system is simpler and the reliability of detection is improved.

[0014] 2. The method of the present invention uses the probe of the present invention to establish a calibration curve for corrosion thinning defects of metal components. When the probe of the present invention is used to detect the metal component to be tested, the quantitative assessment method for corrosion thinning defects of metal components proposed in the present invention can be used to efficiently and quantitatively assess the corrosion thinning defects in different areas of the metal component. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a front view of the probe structure of the present invention.

[0016] Figure 2 This is a top view of the probe structure of the present invention.

[0017] Figure 3 This is a bottom view of the probe structure of the present invention.

[0018] Figure 4 Schematic diagram of the detection system.

[0019] Figure 5 This is a corrosion defect distribution map obtained by using the corrosion thinning quantitative evaluation method of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] like Figure 1 、 Figure 2 and Figure 3As shown, the metal component corrosion and thinning defect detection probe of the present invention includes a matrix array of cube-shaped transparent sealed cabins 1, a matrix array of square coils 4, a white solution 3 within the cube-shaped transparent sealed cabin array 1, and hollow plastic spheres 2. The cube-shaped transparent sealed cabin array 1 is made of transparent material, tightly attached to each other and with the bottom surfaces in the same plane; the square coil array 4 is fixed to the center of the bottom surface of the cube-shaped transparent sealed cabin array 1, with one square coil fixed to the bottom of each cube-shaped sealed cabin, and the sides of the square coil array 4 are parallel to the corresponding sides of the cube-shaped transparent sealed cabin array 1. The outer layer of the hollow plastic sphere 2 is evenly coated with black magnetic powder.

[0022] The method for quantitatively evaluating corrosion thinning defects using a metal component corrosion thinning defect detection probe of the present invention includes establishing a calibration curve for corrosion thinning defects of the metal component and quantitatively evaluating corrosion thinning defects of the metal component;

[0023] (1) Establishment of the calibration curve of corrosion thinning defects of metal components. The specific method is as follows:

[0024] like Figure 4 As shown, a signal generator, a power amplifier, and a square coil array 4 of the detection probe are connected in sequence to form a detection system; a period of T , duty cycle is 50%, amplitude is I The detection probes are closely attached to the thickness of d , 0.9 d , 0.8 d , 0.7 d , 0.6 d , 0.5 d , 0.4 d , 0.3 d , 0.2 d and 0.1 d On the surface of the metal component, since the detection probe will generate different intensities of induced eddy current fields in metal components of different thicknesses, the secondary magnetic fields caused by the induced eddy currents are different, and the total magnetic field intensities are also different. Therefore, the hollow plastic balls 2 corresponding to metal components of different thicknesses are subjected to different downward magnetic forces; at any moment, the hollow plastic balls 2 corresponding to metal components of different thicknesses are at different heights in the cube transparent sealed cabin array 1. When a camera is used to obtain its image, it is reflected in the grayscale images corresponding to the images of metal components of different thicknesses. A camera with a lens surface parallel to the surface of the cube transparent sealed cabin array 1 is fixed above the center of the cube transparent sealed cabin array 1. L 0 and the excitation current is 0.5 T Take pictures at the same time to obtain the grayscale images of 10 metal components in the area of the cube transparent sealed cabin array 1. G1. G 2. G 3. G 4. G 5. G 6. G 7. G 8. G 9 and G 10 , and calculate the average grayscale value of all pixels in the grayscale image g 1. g 2. g 3. g 4. g 5. g 6. g 7. g 8. g 9 and g 10 ;by g 1. g 2. g 3. g 4. g 5. g 6. g 7. g 8. g 9 and g 10 As the horizontal axis, 0, 0.1 d , 0.2 d , 0.3 d , 0.4 d , 0.5 d , 0.6 d , 0.7 d , 0.8 d and 0.9 d As the vertical coordinate, the depth of corrosion thinning defects of metal components is obtained d n and the average gray value g The correlation curve is fitted by quadratic fitting to obtain the fitting formula d n = ag 2 + bg + c ,in a 、 b 、 c are constants respectively;

[0025] (2) Quantitative evaluation of corrosion thinning defects of metal components. The specific methods are as follows:

[0026] like Figure 4As shown, a signal generator, a power amplifier, and a square coil array 4 of the detection probe are connected in sequence, and a period of T , duty cycle is 50%, amplitude is I The detection probe is tightly attached to the surface of the metal component to be tested, and the camera with the lens surface parallel to the surface of the cube transparent sealed cabin array 1 is fixed above the center of the cube transparent sealed cabin array. L 0 and the excitation current is 0.5 T Take pictures at the same time and calculate the average gray value of each sealed cabin area in the cube transparent sealed cabin array 1 g 1，1 、 g 1，2 、 g 1，3 、 g 1，4 、 g 1，5 … g h，j ,in h and j are the rows and columns of the sealed cabin array respectively. The average gray value corresponding to any sealed cabin g i，k Substitute into the formula d n = ag 2 + bg + c The depth of corrosion thinning defects of metal components at any sealed cabin location can be obtained d i，k ,Depend on d 1，1 、 d 1，2 、 d 1，3 、 d 1，4 、 d 1，5 … d h，j A two-dimensional distribution map of the depth of corrosion and thinning defects of metal components at position 1 of the cube transparent sealed cabin array can be obtained.

[0027] Example

[0028] The aluminum alloy plate is inspected by using the metal component corrosion thinning defect detection probe of the present invention. The detection probe is attached to the surface of the aluminum alloy plate and the entire aluminum alloy plate is scanned. The corrosion thinning quantitative evaluation method of the present invention can be used to obtain the following: Figure 5 Corrosion defect distribution diagram shown.

Claims

1. Metal component corrosion thinning defect detection probe, characterized by: The invention comprises a matrix-arranged cubic transparent sealed cabin array (1), a matrix-arranged square coil array (4), and a white solution (3) and a hollow plastic sphere (2) in each cubic transparent sealed cabin in the cubic transparent sealed cabin array (1); the square coil array (4) is fixed at the center of the bottom surface of the cubic transparent sealed cabin array (1), and one square coil is fixed at the bottom of each cubic sealed cabin; the outer layer of the hollow plastic sphere (2) is a uniformly distributed black magnetic powder coating, and the density of the hollow plastic sphere (2) is less than the density of the white solution (3).

2. A metal component corrosion thinning defect detection probe according to claim 1, characterized in that: The cube transparent sealed cabin array (1) is made of transparent material, and the cube transparent sealed cabin arrays (1) are tightly attached to each other and their bottom surfaces are in the same plane; the sides of the square coil array (4) are parallel to the corresponding sides of the cube transparent sealed cabin array (1).

3. A method for quantitatively evaluating corrosion thinning defects of metal components, characterized by: Including the establishment of calibration curves for corrosion thinning defects of metal components and quantitative evaluation of corrosion thinning defects of metal components; (1) Establishment of the calibration curve of corrosion thinning defects of metal components. The specific method is as follows: A signal generator, a power amplifier, and a square coil array (4) of the detection probe according to claim 1 or 2 are sequentially connected to form a detection system; a periodic signal of T , duty cycle is 50%, amplitude is I The detection probes are closely attached to the thickness of d , 0.9 d , 0.8 d , 0.7 d , 0.6 d , 0.5 d , 0.4 d , 0.3 d , 0.2 d and 0.1 d On the surface of the metal component, since the detection probe generates different induced eddy current field strengths in metal components of different thicknesses, the secondary magnetic fields caused by the induced eddy currents are different, and the total magnetic field strengths are also different, the hollow plastic balls (2) corresponding to the metal components of different thicknesses are subjected to different downward magnetic forces; at any moment, the hollow plastic balls (2) corresponding to the metal components of different thicknesses are at different heights in the cube transparent sealed cabin array (1). When the camera is used to obtain its image, it is reflected in the grayscale images of the images corresponding to the metal components of different thicknesses. A camera with a lens surface parallel to the surface of the cube transparent sealed cabin array (1) is fixed above the center of the cube transparent sealed cabin array (1). L 0 and the excitation current is 0.5 T Take pictures at the same time to obtain the grayscale images of the 10 metal components in the area of the cube transparent sealed cabin array (1). G 1. G 2. G 3. G 4. G 5. G 6. G 7. G 8. G 9 and G 10 , and calculate the average grayscale value of all pixels in the grayscale image g 1. g 2. g 3. g 4. g 5. g 6. g 7. g 8. g 9 and g 10 ;by g 1. g 2. g 3. g 4. g 5. g 6. g 7. g 8. g 9 and g 10 As the horizontal axis, 0, 0.1 d , 0.2 d , 0.3 d , 0.4 d , 0.5 d , 0.6 d , 0.7 d , 0.8 d and 0.9 d As the vertical coordinate, the depth of corrosion thinning defects of metal components is obtained d n and the average gray value g The correlation curve is fitted by quadratic fitting to obtain the fitting formula d n = ag 2 + bg + c ,in a 、 b 、 c are constants respectively; (2) Quantitative evaluation of corrosion thinning defects of metal components. The specific methods are as follows: A signal generator, a power amplifier, and a square coil array (4) of the detection probe according to claim 1 or 2 are connected in sequence, and a period of T , duty cycle is 50%, amplitude is I The detection probe is tightly attached to the surface of the metal component to be tested, and a camera whose lens surface is parallel to the surface of the cube transparent sealed cabin array (1) is fixed above the center of the cube transparent sealed cabin array (1). L 0 and the excitation current is 0.5 T Take pictures at the same time and calculate the average gray value of each sealed cabin area in the cube transparent sealed cabin array (1) g 1，1 、 g 1，2 、 g 1，3 、 g 1，4 、 g 1，5 … g h，j ,in h and j are the rows and columns of the sealed cabin array respectively; the average gray value corresponding to any sealed cabin is g i，k Substitute into the formula d n = ag 2 + bg + c Then the depth of corrosion thinning defect of metal components at any sealed cabin location is obtained d i，k ,Depend on d 1，1 、 d 1，2 、 d 1，3 、 d 1，4 、 d 1，5 … d h，j Then, a two-dimensional distribution diagram of the depth of corrosion thinning defects of metal components at the cube transparent sealed cabin array (1) is obtained.

Images