Ferromagnetic metal material surface defect micro-magnetic detection probe with non-conductive coating and device
By designing a micromagnetic detection probe for surface defects of ferromagnetic metal materials with non-conductive coating, using spherical micromagnets and magnetic sensitive detection coils, passive excitation and pollution-free detection are achieved, and detection problems in the prior art are solved. Improve detection accuracy and dynamic range.
Patent Information
- Application Number
- CN202323385580.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-13
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2033-12-13
AI Technical Summary
When existing non-destructive testing technology detects ferromagnetic metal materials with non-conductive coatings, it is difficult to avoid active excitation and pollution, resulting in defect missed detection.
A micromagnetic detection probe for surface defects of ferromagnetic metal material with non-conductive coating is designed, and a spherical micromagnetic and magnetically sensitive detection coil is combined to obtain differential detection signals through micromagnetic disturbances to achieve passive excitation and pollution-free detection.
It realizes high sensitivity detection of surface defects of ferromagnetic metal materials, simple and fast operation, avoids active excitation and pollution, and improves detection accuracy and dynamic range.
Smart Images
Figure CN222189186U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of nondestructive testing, in particular to a micromagnetic detection probe and a micromagnetic detection device for surface defects of ferromagnetic metal materials with non-conductive coatings. Background Art
[0002] Nondestructive testing is an indispensable technical means to ensure the material safety of modern industrial society. Conventional nondestructive testing (NDT) includes five major technologies: ultrasound, X-ray, magnetic powder, eddy current, and penetration. However, in some special applications, the above technologies are all actively excited or pollute the surface of the material and are not allowed to be used. For example, for a component made of ferromagnetic material and having a non-metallic coating on its surface, according to the existing conventional nondestructive testing technology, it is all actively excited or may pollute the surface of the material. In order to prevent accidents, this work has long been able to rely on visual inspection. During the visual inspection process, due to the presence of the coating, internal defects or discontinuities can easily lead to missed inspections. The utility model is developed on the basis of existing technologies, and strives to solve the problem of designing a detection structure suitable for the above working conditions. Utility Model Content
[0003] In order to solve the above problems, the utility model proposes a micro-magnetic detection probe and device for detecting surface defects of ferromagnetic metal materials with non-conductive coatings.
[0004] A micromagnetic detection probe for surface defects of ferromagnetic metal materials with non-conductive coatings, the micromagnetic detection probe is used for detecting surface discontinuities of ferromagnetic metal materials with non-conductive coatings under detection conditions where active excitation is not allowed and contamination of the material surface is not allowed, the micromagnetic detection probe comprises a handle, a housing and a micromagnetic detection assembly;
[0005] The shell is a semi-enclosed shell with an opening, and the opening faces downward, the handle is integrally arranged at the upper end of the shell, and the micromagnetic detection component is embedded in the opening of the shell;
[0006] Among them, the micromagnetic detection component includes a spherical micromagnet and at least two magnetically sensitive detection coils. The lower end of the spherical micromagnet is milled along a circular line to have a horizontal section parallel to the surface of the ferromagnetic metal material. The magnetically sensitive detection coil is embedded in the center position of the horizontal section. The spherical micromagnet slides on the surface of the ferromagnetic metal material, and the two magnetically sensitive detection coils respectively obtain detection signals and form a set of differential detection signals.
[0007] As a further improvement, a mounting groove for the magnetic sensitive detection coil is provided on the horizontal section, and a wiring hole penetrating through the middle of the spherical micro-magnet is provided at the bottom of the mounting groove.
[0008] As a further improvement, the middle part of the handle is hollow and provided with an integrated coupling interface, and the coupling interface corresponds to the wiring hole for engaging the detection line.
[0009] As a further improvement, the shell is adapted to the spherical micro-magnet, and the shell and the spherical micro-magnet are engaged with each other through a clamping block and a clamping groove.
[0010] As a further improvement, the material of the spherical micro-magnet is one of nickel, aluminum, copper, manganese steel, titanium and silicon or other micro-magnetic alloys.
[0011] The utility model also discloses a micromagnetic detection device for surface defects of ferromagnetic metal materials with non-conductive coatings, which adopts any one of the micromagnetic detection probes as described above. The micromagnetic detection device also includes a signal processor and a numerical control display electrically connected to the micromagnetic detection probe; the signal processor includes an operational amplifier and an A / D converter connected in sequence, the operational amplifier outputs a differential detection signal obtained by the magnetic sensitive detection coil of the micromagnetic detection probe and performs analog-to-digital conversion through the A / D converter, and transmits the processing result to the numerical control display.
[0012] Compared with the prior art, the utility model can obtain the following technical effects:
[0013] The utility model adopts the principle of micro-magnetic detection to detect surface defects of ferromagnetic metal materials coated with non-conductive coatings. A micro-magnet with a special structure is designed to move relative to the surface of the ferromagnetic metal material to be detected, generating micro-magnetic disturbances. A highly sensitive magnetic sensitive detection coil is used for detection. The magnetic characteristic signals induced by the movement of the internal magnetic domains and their domain walls during the micro-magnetic disturbance of the ferromagnetic metal material are obtained to determine whether there are defects. The operation is simple, the detection is fast and sensitive, and the detection requirements of no active excitation and no pollution are required under specific working conditions. The specific structural benefits are:
[0014] 1. By setting a semi-enclosed shell and setting a micro-magnet at the opening of the shell, the semi-enclosed shell has a circuit protection space and allows the micro-magnet to better contact with the workpiece to be detected;
[0015] Second, the utility model adopts a spherical micro-magnet, and the lower end of the spherical micro-magnet is milled along the circumference to have a horizontal section parallel to the surface of the ferromagnetic metal material. Based on the principle of micro-magnetic detection, the spherical micro-magnet is moved to perform micro-magnetic disturbance. The horizontal section can better fit the surface of the ferromagnetic metal material, and the curved surface of the spherical micro-magnet is not easy to scratch the surface of the ferromagnetic metal material;
[0016] 3. The utility model has two relatively arranged magnetic sensitive detection coils embedded in the center position of the horizontal section at the lower end of the spherical micro-magnet. The two magnetic sensitive detection coils are symmetrically arranged to form a differential detection structure. This ingenious arrangement not only enhances the coupling effect between the micro-magnetic detection coils and improves immunity to noise, but also effectively offsets the influence of background interference magnetic field, greatly improving the detection accuracy and detection dynamic range of the magnetic sensitive detection coils. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solution in the utility model, a brief introduction is given to the drawings required for use. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.
[0018] Figure 1 It is a schematic diagram of the use state of the utility model.
[0019] Figure 2 It is a schematic diagram of the overall structure of the utility model.
[0020] Figure 3 for Figure 2 Schematic diagram of the structure from another perspective.
[0021] Figure 4 It is the principle diagram of the utility model.
[0022] In the figure, 100-micromagnetic detection probe, 101-spherical micromagnet, 102-mounting slot, 103-micromagnetic detection coil, 104-handle, 105-housing, 200-signal processor, 201-operational amplifier, 202-A / D converter, 300-CNC display, 400-workpiece to be inspected, 401-ferromagnetic metal material, 402-non-conductive coating, 403-discontinuity. DETAILED DESCRIPTION
[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but only represents selected embodiments of the present invention.
[0024] In some special working conditions, it is not allowed to use active excitation detection methods to detect discontinuities on special workpieces, and any contamination of the material surface is not allowed during the detection process. In particular, there has always been great difficulty in detecting surface discontinuities of ferromagnetic metal materials coated with a non-conductive coating. The prior art proposes a micromagnetic detection technology of passive excitation detection based on active excitation detection combined with micromagnetism. The utility model designs a special micromagnetic detection probe based on micromagnetic detection theory, which is intended to be used in the above-mentioned special working conditions to detect surface discontinuities of special materials. The specific contents of the utility model are as follows:
[0025] A micromagnetic detection probe for surface defects of ferromagnetic metal materials with a non-conductive coating. The micromagnetic detection probe 100 is used to detect surface discontinuities 403 of a workpiece 400 to be inspected under detection conditions where active excitation is not allowed and contamination of the material surface is not allowed. The workpiece 400 to be inspected is a ferromagnetic metal material 401 with a non-conductive coating 402. The micromagnetic detection probe 100 includes a handle 104, a shell 105 and a micromagnetic detection component.
[0026] Reference Figure 1-3 , the shell 105 is a semi-enclosed shell with an opening, and the opening faces downward, the handle 104 is integrally arranged at the upper end of the shell 105, and the micromagnetic detection component is embedded in the opening of the shell 104; in this embodiment, the semi-enclosed shell is hemispherical, adapted to the shape of the set micromagnet, and fits with each other, the shell 104 and the spherical micromagnet 101 are engaged with each other through a card block and a card slot. In other embodiments, the shape of the semi-enclosed shell can be further set according to the use environment, which has a accommodating space for the detection line to protect the detection element, and the semi-enclosed shell is provided with an opening, and the micromagnet is arranged at the opening end, so that the micromagnet can better contact with the workpiece to be detected to perform micromagnetic disturbance.
[0027] The micromagnetic detection component includes a spherical micromagnet 101 and at least two magnetically sensitive detection coils 103. The lower end of the spherical micromagnet 101 is milled along a circular line to have a horizontal section parallel to the surface of the ferromagnetic metal material 401. The magnetically sensitive detection coil 401 is embedded in the center position of the horizontal section. The spherical micromagnet 101 slides on the surface of the ferromagnetic metal material 401. The two magnetically sensitive detection coils 103 respectively acquire detection signals and form a set of differential detection signals. In this embodiment, a horizontal section is milled on the lower end of the spherical micromagnet 101, and a micromagnetic detection coil 103 is further embedded in the horizontal section. Compared with the design of directly using the spherical micromagnet 101 and embedding the micromagnetic detection coil 103 at the lower vertex of the spherical micromagnet 101, firstly, the horizontal section enlarges the contact area between the micromagnet and the workpiece to be detected, thereby increasing the magnetic disturbance effect; secondly, the horizontal section is parallel to the surface of the workpiece to be detected and can fit closely, which is more stable during mobile scanning, thereby avoiding detection lift-off or micromagnetic disturbance signal deviation caused by jitter or curved surface sliding.
[0028] Two micromagnetic detection coils 103 are arranged horizontally adjacent to each other to form a differential detection structure. This ingenious arrangement not only enhances the coupling effect between the two micromagnetic detection coils 103 and improves immunity to noise, but also effectively offsets the influence of background interference magnetic field, thereby greatly improving the detection accuracy and detection dynamic range of the magnetic sensor.
[0029] As a further improvement, a mounting groove 102 for the magnetic detection coil 103 is provided on the horizontal section, and a wiring hole that runs through the middle of the spherical micro-magnet is provided at the bottom of the mounting groove 102. The middle of the handle is hollow and provided with an integrated coupling interface, and the coupling interface and the wiring hole are correspondingly connected to the detection line. The detection line of the micromagnetic detection coil 103 passes through the wiring hole and is integrated at the coupling interface. The built-in wiring structure is simple and regular, and can better protect the detection circuit.
[0030] The spherical micromagnet 101 can be selected from any material with weaker magnetic properties than ferromagnetic materials, that is, the magnetization intensity of the spherical micromagnet 101 is much lower than that of ferromagnetic materials, but it can still be guided by the external magnetic field, and its hysteresis loop is narrower than that of ferromagnetic materials, and the saturation magnetic induction intensity is also lower. In this embodiment, the material of the spherical micromagnet is one of nickel, aluminum, copper, manganese steel, titanium and silicon or other micromagnetic alloys.
[0031] Reference Figure 4The utility model also discloses a micromagnetic detection device for surface defects of ferromagnetic metal materials with non-conductive coatings, which adopts any of the micromagnetic detection probes as described above. The micromagnetic detection device also includes a signal processor 200 and a numerical control display 300 electrically connected to the micromagnetic detection probe 100; the signal processor 200 includes an operational amplifier 201 and an A / D converter 202 connected in sequence, and the operational amplifier 201 outputs a differential detection signal obtained by the magnetic sensitive detection coil 103 of the micromagnetic detection probe 100 and performs analog-to-digital conversion through the A / D converter 202, and transmits the processing result to the numerical control display 300.
[0032] The micromagnetic detection probe 100 is used to detect the existence, change, direction, strength of the magnetic field and the physical quantity of the magnetic field change that can be caused. It uses a high-sensitivity magnetic sensitive detection coil in conjunction with a spherical micromagnet to obtain the magnetic characteristic signals induced by the internal magnetic domains and their domain wall movements during the micromagnetic disturbance of the workpiece to be inspected.
[0033] In the utility model, during detection, the horizontal section of the spherical micromagnet 101 is pressed against the surface of the ferromagnetic metal material 401 covered with the non-conductive coating 402, and the spherical micromagnet 101 is moved and scanned to slide on the workpiece 400 to be inspected. When the discontinuity on the surface of the ferromagnetic metal material 401 is detected, the magnetic field changes, and the two highly sensitive micromagnetic detection coils 103 are used to respectively obtain magnetic characteristic signals, and the detection signal imbalance is detected. The operational amplifier 201 amplifies and outputs the differential signal of the two micromagnetic detection coils 103, and the differential signal is converted into digital form by the A / D converter 202, and the converted signal is transmitted to the CNC display 300. Through data analysis and processing, the defect detection information of the workpiece 400 to be inspected is obtained.
[0034] The above description is only the preferred implementation of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.
Claims
1. Micromagnetic detection probe for surface defects of ferromagnetic metal materials with non-conductive coatings. The micromagnetic detection probe is used to detect surface discontinuities of ferromagnetic metal materials with non-conductive coatings under detection conditions where active excitation is not allowed and contamination of the material surface is not allowed. It is characterized by: The micromagnetic detection probe comprises a handle, a shell and a micromagnetic detection component; The shell is a semi-enclosed shell with an opening, and the opening faces downward, the handle is integrally arranged at the upper end of the shell, and the micromagnetic detection component is embedded in the opening of the shell; Among them, the micromagnetic detection component includes a spherical micromagnet and at least two magnetically sensitive detection coils. The lower end of the spherical micromagnet is milled along a circular line to have a horizontal section parallel to the surface of the ferromagnetic metal material. The magnetically sensitive detection coil is embedded in the center position of the horizontal section. The spherical micromagnet slides on the surface of the ferromagnetic metal material, and the two magnetically sensitive detection coils respectively obtain detection signals and form a set of differential detection signals.
2. The micromagnetic detection probe for surface defects of ferromagnetic metal materials with a non-conductive coating according to claim 1, characterized in that: The horizontal section is provided with an installation groove for the magnetic sensitive detection coil, and the bottom of the installation groove is provided with a wiring hole that runs through the middle of the spherical micro-magnet.
3. The micromagnetic detection probe for surface defects of ferromagnetic metal materials with a non-conductive coating according to claim 2, characterized in that: The middle part of the handle is hollow and is provided with an integrated coupling interface, and the coupling interface corresponds to the wiring hole for connecting the detection line.
4. The micromagnetic detection probe for surface defects of ferromagnetic metal materials with a non-conductive coating according to claim 1, characterized in that: The shell is adapted to the spherical micro-magnet, and the shell and the spherical micro-magnet are engaged with each other through a clamping block and a clamping groove.
5. The micromagnetic detection probe for surface defects of ferromagnetic metal materials with a non-conductive coating according to claim 1, characterized in that: The material of the spherical micro-magnet is any micro-magnetic alloy of nickel, aluminum, copper, manganese steel, titanium and silicon.
6. A micromagnetic detection device for surface defects of ferromagnetic metal materials with non-conductive coatings, characterized in that: Using any one of the micromagnetic detection probes described in claims 1 to 5, the micromagnetic detection device also includes a signal processor and a numerical control display electrically connected to the micromagnetic detection probe; the signal processor includes an operational amplifier and an A / D converter connected in sequence, the operational amplifier outputs a differential detection signal obtained by the magnetic sensitive detection coil of the micromagnetic detection probe and performs analog-to-digital conversion through the A / D converter, and transmits the processing result to the numerical control display.