CN112129830A - Aircraft metal structure burn detection method based on eddy current conductivity - Google Patents
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Abstract
The invention discloses an aircraft metal structure burn detection method based on eddy current conductivity, which includes the steps of simulating a burn experiment through heat treatment of a metal structure material to obtain the corresponding relation between the conductivity of the metal structure material and the structural strength and the hardness, establishing a burn evaluation database based on the eddy current conductivity and developing burn detection software by summarizing burn degree evaluation standards, realizing rapid evaluation of the burn degree of the aircraft metal structure, and providing a basis for making an aircraft burn first-aid repair scheme; the method improves the traditional eddy current signal technology such as temperature compensation, lift-off compensation, phase amplitude detection and filtering, forms a conductivity detection device, provides the burn grade standard of the metal structure of the airplane, establishes a burn evaluation database and develops a burn evaluation client, thereby realizing the rapid evaluation of the burn degree of the metal structure of the airplane.
Description
Technical Field
The invention relates to the technical field of aircraft metal structure burn assessment, in particular to an aircraft metal structure burn detection method based on eddy current conductivity.
Background
The metal structure burn of the airplane can be caused when the airplane is hit by an enemy or an oil tank leaks oil and fires, and the like, the metal structure burn of the airplane is the most common damage form of the airplane, and the existing metal structure burn detection system of the airplane in China has the problems of backward detection technology, low detection precision, lack of experimental data support, no burn evaluation standard and the like, and the burn first-aid repair of the metal structure of the airplane is seriously influenced.
The eddy current method is a commonly used measuring method for detecting the conductivity of the metal material, has simple structure, low power consumption, sensitive measurement, rapidness and no damage, and is widely applied to the identification of the heat treatment state and the heat treatment quality inspection of aluminum and titanium alloys.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the method overcomes the defects of the prior art, improves the temperature compensation, lift-off compensation, phase amplitude detection, filtering and other technologies of the traditional eddy current signal, provides the burn grade standard of the airplane metal structure, establishes a burn evaluation database and develops a burn evaluation client, and thus, the airplane metal structure burn detection method realizes the rapid evaluation of the burn degree of the airplane metal structure.
The technical scheme adopted by the invention for solving the technical problem is as follows: a method for detecting burn of an airplane metal structure based on eddy current conductivity comprises the steps of simulating a burn experiment through heat treatment of a metal structure material to obtain the corresponding relation between the conductivity of the metal structure material and the structural strength and hardness, establishing a burn evaluation database based on the eddy current conductivity and developing burn detection software by summarizing burn degree evaluation standards, realizing rapid evaluation of the burn degree of the airplane metal structure, and providing a basis for making an airplane burn emergency repair scheme; the method comprises the following specific steps:
selecting a typical airplane structure material, and performing a burn simulation experiment under corresponding conditions to obtain a burned metal material;
placing the metal material obtained in the step one near a coil magnetic field Hp of an eddy current conductivity detection device, inducing eddy currents on the surface of the material under the action of an alternating magnetic field, generating an alternating counter magnetic field Hs by the eddy currents, and measuring the conductivity of the conductor by measuring the impedance change of the detection coil; the method comprises the following steps in the measuring process:
1) carrying out temperature drift compensation on the eddy current sensor through a compensation technology;
2) carrying out nonlinear compensation on the exponential characteristic of the lift-off effect of the eddy current sensor by adopting an exponential operation circuit;
3) establishing a geometric model of a probe coil of the cylindrical eddy current sensor by adopting ANSYS analysis software of a finite element method according to the basic principle of eddy current detection, analyzing the influence of parameters of the probe coil, and carrying out simulation analysis on the model to realize finite element analysis on the eddy current sensor;
4) performing software denoising by adopting a wavelet grading denoising method through Matlab software to obtain an accurate real signal, and completing wavelet denoising of the eddy current detection signal;
step three, according to the conductivity obtained in the step three, researching the corresponding relation among the conductivity, the strength and the hardness of the metal material in different simulated burn states, and drawing up four different burn degree standards;
step four, based on the metal material performance test results in the step one and the step three, establishing a conductivity-based burn evaluation mathematical model, establishing a conductivity-based burn evaluation database on the SQL Server 2012, and developing, analyzing and diagnosing a client by using Visual Studio 2012 on a Windows platform;
and fifthly, inputting initial information such as the characteristics of the airplane metal material to be detected, inputting the initial information into the client, setting a detection path and a detection method, carrying out corresponding detection calculation, comparing the calculation result with the data of the same type in the burn evaluation database, judging whether the burn exists or not, and determining a detection report.
Further, in the step one, the typical airplane structure material is 7050 aluminum alloy or TC4 titanium alloy, and the corresponding conditions are that the temperature is 250-1150 ℃ and the time is 1-10 min.
Furthermore, in the second step, the impedance change caused by the measurement is converted into a voltage change differential output through a Z/V converter, the voltage change differential output is subjected to detection and filtering adjustment to output a direct current voltage for display, an alternating signal is generated by adopting a DDS technology from the beginning of phase analysis according to a single-frequency impedance method principle and is supplied to a bridge and a detection coil, the signal is amplified, subjected to phase-sensitive detection and filtering to be converted into a direct current signal containing phase information and amplitude information of the coil impedance change, and the direct current signal is input to a computer after being processed.
Further, in the second step, a geometric model of the probe coil of the cylindrical eddy current sensor is modeled by using a two-dimensional model, the meshing of the geometric model is divided by using a mapping network, a regular shape is mapped onto an irregular region, and a PLANE53 unit is selected for meshing of the problem of the planar and axial symmetric magnetic field in analysis, so that higher analysis accuracy is obtained.
Further, in the second step, boundary conditions are set, and a load and a solution are applied, wherein the load refers to the boundary conditions and an external or internal force function, the boundary conditions need to be applied to the sensor shell and a pipeline connected with the sensor shell, a VOLT constraint is applied, the zero potential is set, a magnetic signal is applied to a grid node divided by an air domain to serve as an excitation element, and a wavefront solver is used for accurately obtaining an analysis result.
Further, in the second step, the noise elimination process is processed as follows: firstly, wavelet multi-resolution decomposition is carried out on the signals, and then the noise part is generally contained in three noise frequency bands of CD1, CD2 and CD 3; then processing the wavelet coefficient according to the forms of threshold value and the like; and then reconstructing to achieve the purpose of denoising.
Furthermore, in the second step, the eddy current conductivity detection device comprises a computer, and an excitation signal source, an eddy current sensor, a Z/V transmitter, a voltage follower, an isolation measurement circuit and a subsequent circuit which are connected with the computer;
the excitation signal source is a sine wave generator, which adopts a 10 KHz-1 MHz highly stable sine wave signal generated by a special DDS digital frequency synthesis chip AD9850 and adopts an AGC feedback network to improve the stability of the signal amplitude;
the eddy current sensor is of a cylindrical structure and adopts an upper and lower double-coil structure, the lower coil is a detection element, and the upper coil is a compensation coil;
the Z/V transmitter is an amplifier and a differential circuit.
Furthermore, in the third step, defined by the variation of the strength and the conductivity of the airplane metal structure in the burning process, the standard TC4 titanium alloy test pieces under four different burning grades of I-IV grades are provided, wherein the I grade is not burnt, the II grade is slight burnt, the III grade is medium burnt, and the IV grade is serious burnt.
Further, in the fifth step, the detection report includes component information, material information, a history of the detection component, a display of the detection result, and a diagnosis conclusion.
The invention has the beneficial effects that:
1. the method improves the traditional eddy current signal technology such as temperature compensation, lift-off compensation, phase amplitude detection and filtering, forms a conductivity detection device, provides the burn grade standard of the metal structure of the airplane, establishes a burn evaluation database and develops a burn evaluation client, thereby realizing the rapid evaluation of the burn degree of the metal structure of the airplane.
2. The eddy current conductivity detection device has the advantages of simple structure, low power consumption, high detection precision, good stability, high detection precision and high intelligent degree, has the functions of automatic temperature drift compensation and lift-off compensation, and can provide a basis for making an airplane burn emergency repair scheme.
Description of the drawings:
FIG. 1 is a schematic diagram of eddy current testing of metal conductivity in the method of the present invention.
FIG. 2 is a schematic diagram of a system for measuring an output signal of an eddy current sensor in accordance with the method of the present invention.
FIG. 3 is a schematic diagram of the Z/V conversion temperature compensation technique in the method of the present invention.
FIG. 4 is a schematic diagram illustrating the effect of temperature compensation on the output voltage of a sensor in the method of the present invention.
FIG. 5 is a block diagram of an experimental verification platform for structural optimization of a sensor in the method of the present invention.
FIG. 6 is a front view of an eddy current microsensor structure in accordance with the methods of the present invention.
FIG. 7 is a graphical illustration of the effect of lift-off on sensor output voltage and phase in the method of the present invention.
FIG. 8 is a schematic circuit diagram of the exponential compensation technique of the method of the present invention.
FIG. 9 shows the relationship between the lift-off distance and the output voltage after exponential compensation.
FIG. 10 is a top view of an eddy current microsensor structure in accordance with the methods of the present invention.
FIG. 11 is a schematic software flow diagram of burn detection analysis software in accordance with the method of the present invention.
FIG. 12 is a schematic view of a burn detection procedure in the method of the present invention.
FIG. 13 is a graph of conductivity versus intensity.
FIG. 14 is a graph of conductivity versus hardness.
Detailed Description
Example (b): referring to fig. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 and 14, fig. 6 shows 1 a-the sensing element, 1 b-the compensation coil, 1 c-the frame and 1 d-the core.
The present application will be described in detail below with reference to the drawings and examples.
The method comprises the following steps: performing a burn simulation experiment on 7050 aluminum alloy or TC4 titanium alloy at the temperature of 250-1150 ℃ for 1-10 min.
Step two: providing an eddy current conductivity detection device for an airplane metal structure, wherein the measurement range reaches 0.3-63MS/m, the measurement precision reaches about +/-1 percent, and the error is controlled within 0.5 percent;
as shown in fig. 1, if a metal material is placed near a coil magnetic field Hp, a vortex-like current called eddy current is induced on the surface of the material under the action of an alternating magnetic field, and an alternating counter magnetic field Hs is generated by the eddy current.
FIG. 2 is a schematic block diagram of an eddy current measurement system, in which impedance changes caused by measurement are converted into voltage change differential output through a Z/V converter, and the voltage change differential output is subjected to wave detection and filtering adjustment to output a DC voltage for display;
the excitation signal source is a sine wave generator with high stability, a special DDS digital frequency synthesis chip AD9850 is adopted to generate a 10 KHz-1 MHz high-stability sine wave signal, the frequency stability can reach 10 < -7 > within the temperature range of minus 20 to 60 ℃, and an AGC feedback network is adopted to improve the signal amplitude stability by 10 < -4 >;
aiming at the problem of large temperature drift in the existing burn detection technology, as shown in fig. 3, a Z/V transmitter in the figure is composed of amplifiers U1B and R3, L1 and L2 to form a differential circuit to realize Z/V conversion, U1A and U1C to form a voltage follower, the measurement circuit and a subsequent circuit are isolated, L1 is a measurement coil of the sensor, L2 is a compensation coil, characteristic parameters of the compensation coil are completely the same as those of L1, and L2 automatically compensates the temperature drift caused by the detection coil because the compensation coil L2 and the detection coil L1 are in the same temperature field.
The first experimental verification is as follows:
FIG. 4 is a graph of sensor output voltage measurements taken earlier for a 2mm thick duralumin alloy sheet under no-load and load (with temperature compensation). Under the condition of load (temperature compensation), the output voltage changes along with the temperature to form a horizontal curve which basically does not change along with the temperature;
because the lift-off effect is mainly reflected on the amplitude of the impedance and has little influence on the phase, the item starts from the phase analysis according to the principle of a single-frequency impedance method, an alternating signal is generated by adopting a DDS (direct digital synthesis) technology and is supplied to an electric bridge and a detection coil, the signal is converted into a direct current signal containing phase information and amplitude information of the impedance change of the coil after being amplified, phase-sensitive detected and filtered, and the direct current signal is input into a computer system after being processed, as shown in figure 5;
in order to achieve the maximum sensitivity of the sensor, the sensor should have a cylindrical structure, a double coil is an up-down structure, a lower coil is a detection element, and an upper coil is a compensation coil, as shown in fig. 6 and 10.
And (2) experimental verification:
in the previous experiment, an aluminum alloy with the conductivity of 35.2MS/m is selected as a tested piece to verify the sensor. The results show that increasing the core size can improve the sensor sensitivity to some extent. The method comprises the following steps of using an aluminum alloy as a tested piece, adjusting the distance between a sensor and the tested piece, and simultaneously acquiring amplitude information and phase information, wherein an experimental result is shown in fig. 7, the influence of lift-off within lmm on the phase in the impedance information of the sensor is small, the lift-off is mainly reflected in the amplitude information, and the influence of the lift-off effect on the sensor can be reduced by using the phase;
as can be seen from fig. 7, the lift-off distance and the voltage signal output by the sensor are in a nonlinear relationship, and the nonlinear section of the sensor is linearly compensated by using the exponential operation circuit, so that the sensitivity and the anti-interference performance of the sensor can be maximized on the premise of ensuring the measurement accuracy;
the exponential compensation circuit is designed based on the exponential characteristic of the transistor, as shown in fig. 8. The output voltage is used as a nonlinear compensation link, so that the influence generated by the lift-off effect can be effectively corrected. In order to solve the negative effect that the exponential operation circuit has attenuation on the contrary to a short distance, the output and the input of the exponential operation circuit pass through an integrated operational amplifier subtraction circuit.
And (3) experimental verification:
fig. 9 is a graph showing the relationship between the output voltage and the lift-off distance in the eddy current lift-off effect test performed on the duralumin alloy in the previous stage. After the exponential characteristic correction, the output voltage and the lift-off distance basically have a linear relation, and the lift-off distance is obviously improved;
aiming at the defects of the existing burn detection technology, the software technology to be researched comprises a finite element analysis technology of an eddy current sensor and an eddy current detection signal wavelet denoising technology based on Matlab;
the finite element analysis technology of the eddy current sensor is characterized in that according to the basic principle of eddy current detection, ANSYS analysis software of a finite element method is adopted to establish a geometric model of a probe coil of the cylindrical eddy current sensor, analyze the influence of parameters of the probe coil and perform simulation analysis on the model;
the sensor model is modeled by a two-dimensional model, the grid division of the sensor model is divided by a mapping network, a regular shape is mapped onto an irregular region, and a PLANE53 unit is selected for the grid division of the problem of the planar and axial symmetric magnetic field in the analysis so as to obtain higher analysis precision;
boundary conditions are then set, and the load is applied and solved. Load refers to boundary conditions and external or internal force functions where the sensor housing and associated pipeline are required to impose boundary conditions, impose VOLT constraints, and set to zero potential. Applying magnetic signals on grid nodes divided by an air domain as excitation elements, and accurately obtaining an analysis result by using a wavefront solver;
the research of the noise elimination of the Matlab-based eddy current detection signal by wavelet analysis is to eliminate noise of software by means of higher-level Matlab software by adopting a wavelet grading noise reduction method so as to obtain an accurate real signal and eliminate various interferences;
the noise cancellation process can be handled as follows: firstly, wavelet multi-resolution decomposition is carried out on signals, noise parts are usually contained in three noise frequency bands of CD1, CD2 and CD3, then wavelet coefficients can be processed according to a threshold value and the like, and then reconstruction is carried out, so that the purpose of noise elimination can be achieved.
And (4) experimental verification:
by comparing the original eddy current test signal accompanied with high-frequency noise with the signal subjected to noise elimination processing by using the given soft threshold noise elimination, a satisfactory result is obtained on the aspect of filtering the high-frequency measurement noise by adopting a one-dimensional wavelet reconstruction method, and the purposes of filtering the measurement noise and retaining a useful impedance eddy current signal are achieved.
Step three: performing a burn simulation experiment on the TC4 titanium alloy at the temperature of 250-1150 ℃ for 1-10 min, and then testing the conductivity, strength and hardness of a test piece respectively;
reference data analysis shows that the relationship between the conductivity and the strength of the material is more intuitive, so that the acceptance standard is defined by the variation of the strength and the conductivity in the burn process of the metal structure of the airplane, and TC4 titanium alloy standard test pieces under four different burn grades of I-IV grades are provided, wherein the I grade is not burnt, the II grade is slight burn, the III grade is medium burn, and the IV grade is serious burn.
When the reduction degree of the conductivity is lower than 5 percent and the reduction of the intensity is controlled within 10 percent, the burn is not burnt in the I grade; when the conductivity is reduced to 5-10%, the intensity is reduced within 10-30%, and the skin is a grade II mild burn; when the conductivity is reduced to 10-20%, the strength is reduced to 20-50%, and the burn is grade III moderate burn; when the conductivity drops by more than 20%, the intensity is reduced by more than 50%, which is a severe burn of grade IV.
Step four: a conductivity-based burn assessment mathematical model (sigma b =181.53 kappa-1746.3; H = -15.67 kappa +561.87, wherein sigma b is tensile strength, kappa is conductivity, and H is Brinell hardness) is established, an expert database is used as a support in a control computer, Visual Studio 2012 is used for developing and analyzing diagnostic software on a Windows platform, and the database is developed by SQL Server 2012. The specific functionality comprises hardware parameter configuration and control command issuing, measurement data acquisition and analysis processing, data management and a good human-computer interface.
The hardware parameter configuration and control command issuing is to issue a control command and modify hardware configuration parameters, such as changing the frequency, amplitude, gain control and amplification factor of an excitation source, through a PCI interface; the measurement data acquisition and analysis processing is based on the frequency value of an analog signal acquired by a PCI interface and the count value N measured by a counter, the phase difference pulse width is calculated, and finally the impedance phase of a probe coil and the conductivity value of a tested piece are obtained by adopting a relevant numerical value calculation method; in order to facilitate later-stage experimental data query and processing, calculation results such as measured phase values and conductivity values are stored in real time, and the whole software is required to have high-efficiency data response and processing capacity so as to meet the requirements on the real-time performance and precision of the conductivity measurement of the test piece.
The general flow of the specific analysis software is shown in fig. 11, after logging in the system, a user inputs initial information such as characteristics of an airplane component 7050 aluminum alloy (not shown in an experiment), a TC4 titanium alloy material and the like, sets a detection path, a detection method and the like, performs corresponding detection calculation, compares a calculation result with data of the same type in an expert database, judges whether a burn exists, and determines the type of the burn, the degree of the burn and guidance suggestions.
The specific burn detection process is shown in fig. 12, the detection mainly includes three modules, namely detection start module, defect detection module and detection report generation and output module, wherein the detection start module mainly includes selection of a detection method and a path; burn detection includes burn type identification and determination of burn extent; the detection report mainly comprises component information, material information, historical records of the detection components, display of detection results, diagnosis conclusions and the like.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and all simple modifications, equivalent variations and modifications made to the above embodiment according to the technical spirit of the present invention still fall within the scope of the technical solution of the present invention.
Claims (9)
1. A method for detecting burn of an airplane metal structure based on eddy current conductivity comprises the steps of simulating a burn experiment through heat treatment of a metal structure material to obtain the corresponding relation between the conductivity of the metal structure material and the structural strength and hardness, establishing a burn evaluation database based on the eddy current conductivity and developing burn detection software by summarizing burn degree evaluation standards, realizing rapid evaluation of the burn degree of the airplane metal structure, and providing a basis for making an airplane burn emergency repair scheme; the method comprises the following specific steps:
selecting a typical airplane structure material, and performing a burn simulation experiment under corresponding conditions to obtain a burned metal material;
placing the metal material obtained in the step one near a coil magnetic field Hp of an eddy current conductivity detection device, inducing eddy currents on the surface of the material under the action of an alternating magnetic field, generating an alternating counter magnetic field Hs by the eddy currents, and measuring the conductivity of the conductor by measuring the impedance change of the detection coil; the method comprises the following steps in the measuring process:
1) carrying out temperature drift compensation on the eddy current sensor through a compensation technology;
2) carrying out nonlinear compensation on the exponential characteristic of the lift-off effect of the eddy current sensor by adopting an exponential operation circuit;
3) establishing a geometric model of a probe coil of the cylindrical eddy current sensor by adopting ANSYS analysis software of a finite element method according to the basic principle of eddy current detection, analyzing the influence of parameters of the probe coil, and carrying out simulation analysis on the model to realize finite element analysis on the eddy current sensor;
4) performing software denoising by adopting a wavelet grading denoising method through Matlab software to obtain an accurate real signal, and completing wavelet denoising of the eddy current detection signal;
step three, obtaining the corresponding relation among the conductivity, the strength and the hardness of the metal material under different simulated burn states according to the conductivity obtained in the step two, and drawing up four different burn degree standards;
step four, based on the metal material performance test results in the step one and the step three, establishing a conductivity-based burn evaluation mathematical model, establishing a conductivity-based burn evaluation database on the SQL Server 2012, and developing, analyzing and diagnosing a client by using Visual Studio 2012 on a Windows platform;
and fifthly, inputting initial information such as the characteristics of the airplane metal material to be detected, inputting the initial information into the client, setting a detection path and a detection method, carrying out corresponding detection calculation, comparing the calculation result with the data of the same type in the burn evaluation database, judging whether the burn exists or not, and determining a detection report.
2. The eddy current conductivity based burn detection method for aircraft metal structures according to claim 1, wherein: in the first step, the typical airplane structure material is 7050 aluminum alloy or TC4 titanium alloy, and the corresponding conditions are that the temperature is 250-1150 ℃ and the time is 1-10 min.
3. The eddy current conductivity based burn detection method for aircraft metal structures according to claim 1, wherein: in the second step, the impedance change caused by the measured impedance is converted into voltage change differential output through a Z/V converter, direct current voltage is output through detection and filtering adjustment and displayed, an alternating signal is generated by adopting a DDS technology and is supplied to an electric bridge and a detection coil according to the principle of a single-frequency impedance method and starting from phase analysis, the signal is converted into a direct current signal containing phase information and amplitude information of coil impedance change after amplification, phase-sensitive detection and filtering, and the direct current signal is input into a computer after being processed.
4. The eddy current conductivity based burn detection method for aircraft metal structures according to claim 1, wherein: in the second step, a geometric model of the probe coil of the cylindrical eddy current sensor is modeled by a two-dimensional model, the meshing of the geometric model is divided by a mapping network, a regular shape is mapped onto an irregular region, and a PLANE53 unit is selected for meshing of the problem of the PLanE and axial symmetry magnetic field in analysis, so that higher analysis accuracy is obtained.
5. The eddy current conductivity based burn detection method for aircraft metal structures according to claim 1, wherein: in the second step, boundary conditions are set, and load and solution are applied, wherein the load refers to the boundary conditions and an external or internal acting force function, the boundary conditions need to be applied to the sensor shell and a pipeline connected with the sensor shell, VOLT constraint is applied, zero potential is set, magnetic signals are applied to grid nodes divided by an air domain to serve as excitation elements, and a wavefront solver is used for accurately obtaining analysis results.
6. The eddy current conductivity based burn detection method for aircraft metal structures according to claim 1, wherein: in the second step, the noise elimination process is processed according to the following method: firstly, wavelet multi-resolution decomposition is carried out on the signals, and then the noise part is generally contained in three noise frequency bands of CD1, CD2 and CD 3; then processing the wavelet coefficient according to the forms of threshold value and the like; and then reconstructing to achieve the purpose of denoising.
7. The eddy current conductivity based burn detection method for aircraft metal structures according to claim 1, wherein: in the second step, the eddy current conductivity detection device comprises a computer, and an excitation signal source, an eddy current sensor, a Z/V transmitter, a voltage follower, an isolation measurement circuit and a subsequent circuit which are connected with the computer;
the excitation signal source is a sine wave generator, which adopts a 10 KHz-1 MHz highly stable sine wave signal generated by a special DDS digital frequency synthesis chip AD9850 and adopts an AGC feedback network to improve the stability of the signal amplitude;
the eddy current sensor is of a cylindrical structure and adopts an upper and lower double-coil structure, the lower coil is a detection element, and the upper coil is a compensation coil;
the Z/V transmitter is an amplifier and a differential circuit.
8. The eddy current conductivity based burn detection method for aircraft metal structures according to claim 1, wherein: and in the third step, the variable quantities of the strength and the conductivity of the airplane metal structure in the burning process are defined, and TC4 titanium alloy standard test pieces under four different burning grades of I-IV grades are provided, wherein the I grade is not burnt, the II grade is slight burn, the III grade is medium burn, and the IV grade is serious burn.
9. The eddy current conductivity based burn detection method for aircraft metal structures according to claim 1, wherein: in the fifth step, the detection report comprises component information, material information, historical records of the detection component, display of the detection result and a diagnosis conclusion.
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| CN112966354A (en) * | 2021-03-29 | 2021-06-15 | 湖北三江航天江北机械工程有限公司 | Anti-scouring capability assessment method for gas flow drainage device |
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| CN112966354A (en) * | 2021-03-29 | 2021-06-15 | 湖北三江航天江北机械工程有限公司 | Anti-scouring capability assessment method for gas flow drainage device |
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| CN113740506A (en) * | 2021-08-26 | 2021-12-03 | 成都飞机工业（集团）有限责任公司 | In-situ evaluation method for titanium alloy burned tissue |
| CN113740506B (en) * | 2021-08-26 | 2022-08-12 | 成都飞机工业（集团）有限责任公司 | In-situ evaluation method for titanium alloy burned tissue |
| CN118010953A (en) * | 2024-04-09 | 2024-05-10 | 徐州赛威机械制造科技有限公司 | Intelligent test method and system for metal structure manufacturing |
| CN118010953B (en) * | 2024-04-09 | 2024-06-07 | 徐州赛威机械制造科技有限公司 | Intelligent test method and system for metal structure manufacturing |
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