A weak magnetic defect detection system for ferromagnetic materials

Abstract

The present invention relates to a weak magnetic defect detection system for ferromagnetic materials. The system comprises: an STM32 single chip microcomputer, a photoelectric encoder and a weak magnetic sensor; the STM32 single chip microcomputer is respectively connected to the photoelectric encoder and the weak magnetic sensor; the weak magnetic sensor is used to collect weak magnetic signals of devices made of ferromagnetic materials; the photoelectric encoding is arranged on a mileage wheel, and the photoelectric encoder is used to collect displacement pulse signals; the STM32 single chip microcomputer is used to combine the weak magnetic signal and the displacement pulse signal so that the weak magnetic signal corresponds to the displacement pulse signal; when the weak magnetic sensor detects a defect of the device made of the ferromagnetic material, the defect position of the device made of the ferromagnetic material is determined based on the real-time corresponding relationship between the weak magnetic signal and the displacement pulse signal. The present invention can reduce the error between the weak magnetic signal and the defect position, and improve the detection efficiency and detection quality.

Description

Technical Field

[0001] The invention relates to the field of industrial nondestructive testing, and in particular to a weak magnetic defect detection system for ferromagnetic materials. Background Art

[0002] Weak magnetic detection technology can be widely used in the field of industrial nondestructive testing of ferromagnetic materials such as pipelines, automobiles, and aerospace. Taking the ferromagnetic material gathering and transportation pipeline as an example, the current mainstream weak magnetic nondestructive testing technology in the industry mainly detects whether there are defects in the pipeline based on the magnetic signal collected by the sensor and the total mileage. It detects the stress concentration area, geometric deformation, metal corrosion cracking and other damage of the pipeline, and determines the location of the defect in the pipeline, and finally makes a detection analysis report through the host computer software. However, the above method has certain limitations. Because the magnetic signal and mileage of the weak magnetic detection data acquisition system are collected independently, there is no joint relationship between the two, which leads to errors in the magnetic signal and defect position detected by the system, affecting the detection efficiency and detection quality, and causing trouble for pipeline excavation verification. Summary of the invention

[0003] The purpose of the present invention is to provide a weak magnetic defect detection system for ferromagnetic materials to solve the problems of errors between weak magnetic signals and defect positions, and low detection efficiency and detection quality.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] A ferromagnetic material weak magnetic defect detection system, comprising: an STM32 single chip microcomputer, a photoelectric encoder and a weak magnetic sensor;

[0006] The STM32 single-chip computer is respectively connected to the photoelectric encoder and the weak magnetic sensor; the weak magnetic sensor is used to collect weak magnetic signals of devices made of ferromagnetic materials; the photoelectric encoding is arranged on the mileage wheel, and the photoelectric encoder is used to collect displacement pulse signals; the STM32 single-chip computer is used to combine the weak magnetic signal and the displacement pulse signal so that the weak magnetic signal corresponds to the displacement pulse signal; when the weak magnetic sensor detects a defect in the device made of ferromagnetic materials, the defect position of the device made of ferromagnetic materials is determined based on the real-time corresponding relationship between the weak magnetic signal and the displacement pulse signal.

[0007] Optionally, it also includes: a host computer;

[0008] The host computer is connected to the STM32 single-chip computer; the STM32 single-chip computer uploads the weak magnetic signal and the displacement pulse signal to the host computer for waveform display;

[0009] When the weak magnetic sensor does not detect the defect of the device made of ferromagnetic material, the waveform shows a smooth straight line. When the weak magnetic sensor detects the defect of the device made of ferromagnetic material, the waveform shows obvious fluctuations. When the weak magnetic sensor leaves the defect, the waveform returns to a smooth straight line.

[0010] Optionally, it further includes: the weak magnetic sensor is a Hall sensor; a filter noise reduction and amplification module is provided in the Hall sensor, and the filter noise reduction and amplification module is connected to the STM32 single-chip microcomputer. The filter noise reduction and amplification module is used to perform filter noise reduction and amplification processing on the weak magnetic signal.

[0011] Optionally, a timer is provided in the photoelectric encoder. The timer is connected to the STM32 single-chip microcomputer. The timer is used to increment the count by one when the displacement pulse signal is interrupted and obtain the acquisition time of the weak magnetic sensor.

[0012] Optionally, it further includes: a power supply module and a voltage stabilization module;

[0013] The power supply module is connected to the voltage stabilization module, and the voltage stabilization module is connected to the STM single-chip microcomputer.

[0014] Optionally, it further includes: a data memory;

[0015] The data memory is connected to the STM single-chip microcomputer.

[0016] Optionally, an LED signal lamp;

[0017] The LED signal lamp is connected to the STM single-chip microcomputer. The LED signal lamp is used to indicate whether the weak magnetic defect detection system for ferromagnetic materials is working properly.

[0018] Optionally, it further includes an A / D analog-to-digital converter and a three-state output 8D latch;

[0019] The A / D analog-to-digital converter is respectively connected to the weak magnetic sensor and the STM single-chip microcomputer;

[0020] The three-state output 8D latch is respectively connected to the A / D analog-to-digital converter and the STM single-chip microcomputer.

[0021] Optionally, it further includes: an interference filtering circuit;

[0022] The interference filtering circuit is connected to the STM single-chip microcomputer.

[0023] Optionally, it further includes: a crystal oscillator circuit;

[0024] The crystal oscillator circuit is connected to the STM single chip microcomputer.

[0025] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects: the present invention provides a weak magnetic defect detection system for ferromagnetic materials, in which the weak magnetic signal collected by the weak magnetic sensor and the total mileage are no longer in an independent working state, and the weak magnetic signal collected by the weak magnetic sensor is combined with the displacement pulse signal collected by the encoder fixed in the mileage wheel through a single-chip microcomputer, and there is a real-time corresponding relationship between the weak magnetic signal collected by the weak magnetic sensor and the displacement pulse signal collected by the encoder, so that when the weak magnetic sensor detects a pipeline defect, the defect position of the device made of ferromagnetic material is directly determined based on the real-time corresponding relationship between the weak magnetic signal and the displacement pulse signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 A circuit diagram of a ferromagnetic material weak magnetic defect detection system provided by the present invention;

[0028] Figure 2 This is an operation flow chart of a ferromagnetic material weak magnetic defect detection system provided by the present invention;

[0029] Figure 3 A structural diagram of a ferromagnetic material weak magnetic defect detection system provided by the present invention in practical application;

[0030] Figure 4 This is a structural block diagram of a ferromagnetic material weak magnetic defect detection system provided by the present invention;

[0031] Figure 5 Flow chart of the encoder provided by the present invention;

[0032] Figure 6 This is the LED flow chart provided by the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in 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 ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The purpose of the present invention is to provide a weak magnetic defect detection system for ferromagnetic materials, which can reduce the error between the weak magnetic signal and the defect position and improve the detection efficiency and detection quality.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] A weak magnetic detection data optimization acquisition system, comprising: an STM32 single chip microcomputer, a photoelectric encoder and a weak magnetic sensor;

[0037] The STM32 single-chip computer is respectively connected to the photoelectric encoder and the weak magnetic sensor; the weak magnetic sensor is used to collect weak magnetic signals of devices made of ferromagnetic materials; the photoelectric encoding is arranged on the mileage wheel, and the photoelectric encoder is used to collect displacement pulse signals; the STM32 single-chip computer is used to combine the weak magnetic signal and the displacement pulse signal so that the weak magnetic signal corresponds to the displacement pulse signal; when the weak magnetic sensor detects a defect in the device made of ferromagnetic materials, the defect position of the device made of ferromagnetic materials is determined based on the real-time corresponding relationship between the weak magnetic signal and the displacement pulse signal.

[0038] Figure 1 The invention provides a circuit diagram of a weak magnetic defect detection system for ferromagnetic materials, which includes an STM32 single-chip minimum system control unit 1, a crystal oscillator circuit 2, a three-state output 8D latch 3, an A / D analog-to-digital converter 4, a Hall probe 5, an indicator light circuit 6, an interference filtering circuit 7, a storage circuit 8, a program data download circuit 9, a photoelectric encoder circuit 10, and a power supply voltage stabilization circuit 11.

[0039] VDDA is used as an analog power supply. When performing digital-to-analog or analog-to-digital signal conversion, the system will use VDDA as a reference voltage. VDD is the main power supply and is also the input power supply for the output level of the IO port. In order to ensure the stability of the output voltage, the present invention is also equipped with a power supply voltage stabilization circuit. The single-chip computer voltage stabilization module is composed of a power conversion chip and a capacitor device; the operating voltage of the STM32F103 series microcontroller is between +2.0 and +3.6V. Since the commonly used power supply is 5V, a power conversion chip is used to convert the input 5V voltage to 3.3V voltage, and a capacitor is used to stabilize the voltage. The external device voltage stabilization module is composed of a power conversion chip and capacitors, inductors, and diode devices. The power conversion chip, capacitors, and capacitors convert the external voltage of 24V to a stable 5V voltage for power supply, and a diode is used to prevent reverse connection to avoid burning the circuit board when the polarity of the external DC power supply is connected incorrectly.

[0040] The BOOT0 function is to set the startup mode. When BOOT0 is set to 0, the code will start from the main Flash and can work properly after power-on. BOOT0 is grounded through a 10k resistor R3 to facilitate serial port downloading. The downloader controls BOOT0 to be at a high level and then restores BOOT0 to a low level after downloading. After the STM32 resets, it can enter the user program. PA5 and PA6 are connected to the A-phase and B-phase of the optical encoder, serving as External Interrupt 0 and External Interrupt 1 respectively. The interrupt mode is triggered by a change in level.

[0041] PA9 and PA10 are connected to UART1_TX and UART1_RX as a serial port debugging circuit, aiming to input and output information to locate the working state of the hardware.

[0042] PA13 and PA14 are connected to the SWDIO data line and the SWICK clock line as a program data download port, which is more concise than JTAG. SWDIO: Serial Data Input / Output, used for reading and writing data, serving as a bidirectional data signal line for simulation signals, with a pull-up 10K resistor R21.

[0043] SWCLK: Serial Clock Input, providing the required clock signal, with a pull-up 10K resistor R20. The model 24C04 EEPROM memory chip is transmitted serially. It has 7-bit addresses, one read / write bit (R / W), 1 for read operation and 0 for write operation; one write protection bit WP (write protect), generally connected to a low level (grounded) for reading and writing; one is the SCL clock signal line, and the other is the SDA data signal line.

[0044] The PB6 and PB7 pins are connected to SCL and SDA, and pulled up by 10K resistors R6 and R7 for data storage. NRST represents the reset pin, externally connected to a 100nf capacitor C10 and a 10K resistor R17, whose function is to reset the single-chip microcomputer program. When the NRST pin inputs a low level, all register states except for the backup area registers are restored to their original states.

[0045] PD0 and PD1 are externally connected to OSCIN and OSCOUT of the crystal oscillator circuit 2. The high-speed external crystal oscillator circuit 2 includes X1 - 8MHz, a 1M resistor R22, and 22pF capacitors C17 and C18, providing the instruction time reference.

[0046] PC0~PC8 are externally connected to 8 channels of analog quantities to share A / D for data conversion. The tri-state output latch is used to latch the digital quantity after A / D conversion. When the OE terminal is at a high level, the converted data can be taken from the tri-state output latch.

[0047] ALE is the address latch enable input line, and ADD-A, ADD-B, and ADD-C are address input lines, which are used to select one of the analog inputs on IN0 - IN7. When the ALE line is at a high level, the address latch and decoder latch the address signals on the three address lines ADD-A, ADD-B, and ADD-C, and after decoding, the analog quantity of the selected channel is converted by the converter.

[0048] EOC is the conversion end signal. When EOC is at a high level, it indicates that the conversion is completed; otherwise, it indicates that the A / D conversion is in progress.

[0049] OE is the output enable signal, which is used to control the three output latches to output the converted data to the single-chip microcomputer. When OE = 1, the converted data is output; when OE = 0, the output data line is in a high-impedance state.

[0050] PC10 is externally connected to the LED indicator circuit 6, which is used to indicate the normal working condition of the system. When the PC10 pin outputs a low level, the LED lights flash to indicate that normal operation can be carried out.

[0051] VSS and VSSA are the common ground terminal voltages of the circuit. The parallel capacitors C13, C14, C15, and C16 are used to filter out the interference signals in the power supply of each unit circuit.

[0052] Taking a pipeline made of ferromagnetic material as an example, Figure 2 This is the operation flow chart of a weak magnetic defect detection system for ferromagnetic materials provided by the present invention. The entire system operation program consists of 6 steps: power supply voltage stabilization; system initialization; signal acquisition; signal filtering, amplification, and noise reduction; signal processing by the STM32 single-chip microcomputer; and upper computer display.

[0053] In the first step, the 24V voltage is converted to 5V through the voltage stabilization module, and the 5V voltage is converted to 3.3V to start powering each module.

[0054] In the second to fourth steps, the system is initialized. The Hall probe 5 collects magnetic signals, and the magnetic signals are amplified, filtered, and noise-reduced. The photoelectric encoder collects displacement signals, and the timer collects time signals.

[0055] In the fifth to sixth steps, the collected magnetic signals and angular displacement signals are sent to the upper computer through the serial communication of the single-chip microcomputer for waveform display. When the probe does not detect a defect, the waveform displayed on the upper computer is a relatively smooth straight line. Due to the relatively rough interior of the pipeline, the waveform will have slight fluctuations. When the probe detects a defect, the waveform on the upper computer will have obvious fluctuations. When the probe leaves the detection defect range, the curve waveform returns to the previous straight state.

[0056] Figure 3The structural diagram of a weak magnetic defect detection system for ferromagnetic materials provided by the present invention in practical applications. The schematic diagram includes: pipeline 3-1, leather cup 3-2, probe 3-3, probe bracket 3-4, computer section 3-5, odometer wheel 3-6, fixed bracket 3-7, encoder 3-8.

[0057] Figure 4 The structural block diagram of a weak magnetic defect detection system for ferromagnetic materials provided by the present invention. The system includes an STM32 single-chip microcomputer minimum system control unit, a power supply module, a sensor, an A / D conversion module, a reset / interrupt control module, an encoder module, and a data parameter storage module.

[0058] Figure 5 The encoder flowchart provided by the present invention, as Figure 5 shown.

[0059] Step 1: Define the interface, connect the EN1 interface to GPIO_Pin_5, and the EN2 - B phase interface to GPIO_Pin_6.

[0060] Configure the timer, define the interface: A phase|B phase GPIO_Pin = GPIO_Pin5|GPIO_Pin6; input the parameter values in TIM_TimeBaseStruct: TIM_TimeBaseStructInit; enable the TIM clock: RC_APB1PeriphClockCmd(RCC_APB1Periph_TIM, ENABLE); set the counter reload value: TIM_TimeBaseStructure.TIM_Period = 4095; TIM timer clock prescaler value: TIM_TimeBaseStructure.TIM_Prescaler = 0; set the TIM timer clock division: TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; TIM up - counting: TIM_TimeBaseStructure.TIM_CounterMode = TIM CounterMode Up; interrupt setting:

[0061] TIM_ITConfig(TIM, TIM_IT_Update, ENABLE); NVIC_InitStructure.NVIC_IRQChannel = TIM_IRQn; NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x01; NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01; NVIC_InitStru

[0062] cture.NVIC_IRQChannelCmd = ENABLE;

[0063] Steps 2 to 7: Enter the While loop, trigger the external interrupt, GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource). When EN1 gets a rising edge, the external interrupt starts. At this time, signal reading is performed. If it is a high-level signal, it rotates forward; if it is a low-level signal, it rotates in reverse. The counter time has an interrupt:

[0064] int circle_count = 0; void TIM4_IRQHandler() { if (TIM_GetITStatus(TIM4, TIM_IT_Update) == SET) { if ((TIM4->CR1 >> 4 & 0x01) DIR == 0) circle_count++; else if ((TIM4->CR1 >> 4 & 0x01) DIR == 1) circle_count--; TIM_ClearITPendingBit(TIM4, TIM_IT_Update);}

[0065] Assume that the mileage corresponding to one revolution of the mileage wheel for the internal detector is L meters. Define sum as the encoder counting function. One revolution of the encoder is 60, that is, sum = 60. There is a corresponding proportional relationship between the designed encoder and the mileage wheel, that is, the sum corresponding to one revolution of the mileage wheel is 60K, where K is the number of encoder revolutions corresponding to one revolution of the mileage wheel. Define N as the size of the encoder sum value corresponding to the mileage traveled by the mileage wheel in the pipeline, that is, the displacement X = L * N / 60 * K. The timer is timed every T / ms. After the timing is completed, it is accumulated through count. The speed speed is obtained by calculating based on the timer's counting every T / ms and the real-time displacement, that is, speed = X / T.

[0066] Figure 6The LED flow chart provided by the present invention. The LED lamp operation program consists of 4 steps: enabling the IO clock; initializing the IO port parameters; setting the PC10 port to push-pull up general output mode; setting the PC10 port to low level effective.

[0067] In the first step, enable the IO port clock. Call the function RCC_APB2PeriphColckCmd().

[0068] In the second step, initialize the IO port mode. Call the function GPIO_Init().

[0069] In the third step, operate the IO port and set the PC10 port to push-pull up general output mode.

[0070] In the fourth step, set the IO port and set the PC10 port to low level output mode.

[0071] In addition, the encoder is set with a timer counting function. Each time an interruption occurs, the count is incremented once, so that the acquisition time corresponding to the internal detector can be obtained. And through the speed calculation formula, the acquisition speed corresponding to the internal detector can be indirectly obtained. The embodiments of the present invention optimize the functions of the detection and acquisition system of the device made of ferromagnetic materials, realize the precise evaluation of pipeline defects, reduce the risk of pipeline undetected, improve the detection efficiency and accuracy, narrow the scope of troubleshooting, have a wide application and high applicability, provide greater convenience for the staff while reducing the maintenance cost, and have important practical guiding significance.

[0072] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0073] In this article, specific examples are used to elaborate the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. At the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A weak magnetic defect detection system for ferromagnetic materials, characterized in that, include: STM32 microcontroller, photoelectric encoder and weak magnetic sensor; The STM32 single-chip computer is respectively connected to the photoelectric encoder and the weak magnetic sensor; the weak magnetic sensor is used to collect weak magnetic signals of devices made of ferromagnetic materials; the photoelectric encoding is arranged on the mileage wheel, and the photoelectric encoder is used to collect displacement pulse signals; the STM32 single-chip computer is used to combine the weak magnetic signal and the displacement pulse signal so that the weak magnetic signal corresponds to the displacement pulse signal; when the weak magnetic sensor detects a defect of the device made of ferromagnetic materials, the defect position of the device made of ferromagnetic materials is determined based on the real-time correspondence between the weak magnetic signal and the displacement pulse signal; Assume that the mileage of the internal detector corresponding to one rotation of the odometer wheel is L meters, define sum as the encoder counting function, and one rotation of the encoder is 60, that is, sum=60; there is a corresponding proportional relationship between the designed encoder and the odometer wheel, that is, the sum corresponding to one rotation of the odometer wheel is 60K, and K is the number of encoder rotations corresponding to one rotation of the odometer wheel; define N as the encoder sum value corresponding to the mileage of the odometer wheel in the pipeline, that is, displacement X=L*N / 60*K; the timer counts once every T / ms, and counts after the timing is completed; the speed speed is obtained by calculating the timer counting once every T / ms and the real-time displacement, that is, speed=X / T; The encoder has a built-in timer counting function. Every time it is interrupted, the count is added once to obtain the acquisition time corresponding to the internal detector, and the acquisition speed corresponding to the internal detector is indirectly obtained through the speed calculation formula; Step 1: Define the interface, connect EN1-interface to GPIO_Pin_5, and connect EN2-B phase interface to GPIO_Pin_6; Configure the timer and define the interface: Phase A | Phase B GPIO_Pin = GPIO_Pin5 | GPIO_Pin6; Enter the parameter values ​​in TIM_TimeBaseStruct: TIM_TimeBaseStructInit; Enable TIM clock: RC_APB1PeriphClockCmd (RCC_APB1Periph_TIM, ENABLE); Set the counter reload value: TIM_TimeBaseStructure.TIM_Period = 4095; TIM timing clock prescaler value: TIM_TimeBaseStructure.TIM_Prescaler = 0; Set TIM timer clock division: TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; TIM count up: TIM_TimeBaseStructure.TIM_CounterMode = TIM CounterMode Up; Interrupt setting: TIM_ITConfig(TIM, TIM_IT_Update, ENABLE); NVIC_InitStructure.NVIC_IRQChannel = TIM_IRQn; NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x01; NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01; NVIC_InitStru cture.NVIC_IRQChannelCmd = ENABLE; Steps 2 to 7: Enter the While loop, trigger the external interrupt, GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource). When EN1 gets a rising edge, the external interrupt starts. At this time, signal reading is performed. If it is a high-level signal, it rotates forward; if it is a low-level signal, it rotates in reverse; Interrupt occurs for the counter time: int circle_count = 0; void TIM4_IRQHandler() { if (TIM_GetITStatus(TIM4, TIM_ITUpdate) == SET) { if ((TIM4->CR1 >> 4 & 0x01) && DIR == 0) circle_count++; else if ((TIM4->CR1 >> 4 & 0x01) && DIR == 1) circle_count--; TIM_ClearITPendingBit(TIM4, TIM_IT_Update);}} It further includes: a host computer; the host computer is connected to the STM32 single-chip microcomputer; the STM32 single-chip microcomputer uploads the weak magnetic signal and the displacement pulse signal to the host computer for waveform display; When the weak magnetic sensor does not detect the defect of the device made of ferromagnetic material, the waveform shows a smooth straight line. When the weak magnetic sensor detects the defect of the device made of ferromagnetic material, the waveform fluctuates significantly. When the weak magnetic sensor leaves the defect, the waveform returns to a smooth straight line.

2. The weak magnetic defect detection system for ferromagnetic materials according to claim 1, characterized in that, It further includes: The weak magnetic sensor is a Hall sensor; a filter noise reduction and amplification module is provided inside the Hall sensor, and the filter noise reduction and amplification module is connected to the STM32 single-chip microcomputer. The filter noise reduction and amplification module is used to perform filter noise reduction and amplification processing on the weak magnetic signal.

3. The weak magnetic defect detection system for ferromagnetic materials according to claim 1, characterized in that, A timer is provided inside the optical encoder, and the timer is connected to the STM32 single-chip microcomputer. The timer is used to increment the count by one when the displacement pulse signal is interrupted and obtain the acquisition time of the weak magnetic sensor.

4. The weak magnetic defect detection system for ferromagnetic materials according to claim 1, characterized in that, It further includes: A power supply module and a voltage stabilizing module; The power supply module is connected to the voltage stabilization module, and the voltage stabilization module is connected to the STM single-chip microcomputer.

5. The weak magnetic defect detection system for ferromagnetic materials according to claim 1, characterized in that, It further includes: A data memory; The data memory is connected to the STM single-chip microcomputer.

6. The weak magnetic defect detection system for ferromagnetic materials according to claim 1, characterized in that, An LED signal lamp; The LED signal lamp is connected to the STM single-chip microcomputer, and the LED signal lamp is used to indicate whether the ferromagnetic material weak magnetic defect detection system is working properly.

7. The weak magnetic defect detection system for ferromagnetic materials according to claim 1, characterized in that, It further includes an A / D analog-to-digital converter and a three-state output 8D latch; The A / D analog-to-digital converter is respectively connected to the weak magnetic sensor and the STM single-chip microcomputer; The three-state output 8D latch is respectively connected to the A / D analog-to-digital converter and the STM single-chip microcomputer.

8. The weak magnetic defect detection system for ferromagnetic materials according to claim 1, characterized in that, It further includes: An interference filtering circuit; The interference filtering circuit is connected to the STM single-chip microcomputer.

9. A weak magnetic defect detection system for ferromagnetic materials according to claim 1, characterized in that It further includes: A crystal oscillator circuit; The crystal oscillator circuit is connected to the STM single-chip microcomputer.

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