CN108866547A - A kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning - Google Patents
A kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning Download PDFInfo
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- CN108866547A CN108866547A CN201811060395.9A CN201811060395A CN108866547A CN 108866547 A CN108866547 A CN 108866547A CN 201811060395 A CN201811060395 A CN 201811060395A CN 108866547 A CN108866547 A CN 108866547A
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- laser
- electric spark
- laser cleaning
- cleaning
- magnetic body
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Classifications
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
- C23C26/02—Coating not provided for in groups C23C2/00 - C23C24/00 applying molten material to the substrate
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G5/00—Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents
Abstract
The invention discloses a kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning, includes the following steps：It is the preparation of electrode material first, followed by neodymium iron boron magnetic body is pre-processed using laser cleaning technique, be finally that electrospark impregnation processing is carried out to the magnet surface after laser cleaning, finally prepares the high anti-corrosion protective coating of high-bond in magnet surface.Wherein, laser cleaning is a kind of environmentally protective cleaning way, with cleaning efficiency height, it is simple to operation, it is non-contact, without grinding, without fuel factor and be suitable for the cleaning characteristics such as various specifications magnet, the various types of pollutants of magnet surface can be removed, the cleannes routinely cleaned and be unable to reach are reached.It is very secured for metallurgical bonding between the corrosion-inhibiting coating and matrix of THE ELECTRIC SPARK STRENGTHENING TECHNIQUE preparation, it will not peel off.And THE ELECTRIC SPARK STRENGTHENING TECHNIQUE is simple to operation, electrode material range of choice is wide, is a kind of environmentally friendly magnet surface guard technology.
Description
Technical field
The present invention relates to Nd-Fe-B series permanent magnet technical field, specially a kind of neodymium-iron-boron body surface based on laser cleaning
Face electrospark impregnation processing method.
Background technique
Sintered NdFeB magnet is referred to as contemporary " magnetic king " due to excellent remanent magnetism, coercivity and magnetic energy product, produces
Product are widely used in the fields such as all kinds of motors, medical instrument, hardware appliance, wind-power electricity generation, aerospace and defence and military.But
Sintered NdFeB magnet has very poor corrosion resistance, seriously limits the application field of magnet.Currently, in industrial production usually
The corrosion resisting property of magnet is improved using surface protection process, and matrix must be carried out before magnet surface coating protective layer
Surface treatment generallys use chemical attack cleaning (i.e. alkali cleaning oil removing, acid pickling and rust removing) and high frequency ultrasound cleaning to remove magnet table
The greasy dirt and oxide skin in face.This cleaning method is a kind of cleaning of contact, damages medium (such as the acid of magnet surface and cleaning
Hydrogen ion when washing) it is attached to neodymium iron boron matrix surface, it not can be removed, subsequent plating layer can be had an impact, and chemical attack is clear
The waste liquor contamination environment that washing lotion generates, does not meet current environmental requirement.Therefore, it finds environmentally friendly and does not have to matrix table magnetic
Damaging cleaning way is current urgent problem to be solved.
Currently, Sintered NdFeB magnet surface protection mainly includes the works such as plating, chemical plating, ability cathode electrophoresis, phosphatization
Process.These safeguard procedures belong to all need for magnet to be placed in plating solution when wet process plating scope, i.e. plating, due to being sintered neodymium iron
Boron magnet is prepared by powder metallurgical technique, is had part plating solution and is remained in influence coating matter in the gap of matrix skin
Amount does not have due protection effect, and the waste liquid generated pollutes the environment.Therefore, for current Sintered NdFeB magnet table
The problems such as environmental pollution existing for the wet process depositing process that face protection uses and undesirable anti-corrosion effect, urgent need develop a kind of environment friend
Good type and the neodymium iron boron magnetic body surface protection coating anti-corrosion with high-bond height.
Summary of the invention
The purpose of the present invention is to provide a kind of neodymium iron boron magnetic body electric spark on surface intensive treatment side based on laser cleaning
Method, to solve the problems mentioned in the above background technology.
To achieve the above object, the present invention provides the following technical solutions：A kind of neodymium-iron-boron body surface based on laser cleaning
Face electrospark impregnation processing method, includes the following steps：
(1) selection of electrode material：Elemental metals or multicomponent alloy may be selected as electrode material；
(2) laser cleaning：Sintered NdFeB magnet is surface-treated using laser cleaning technique, removes magnet surface
Greasy dirt and oxide skin；
(3) magnet surface intensive treatment：Using THE ELECTRIC SPARK STRENGTHENING TECHNIQUE, the deposit electrode material that will be selected in step (1)
On Sintered NdFeB magnet surface in step (2) after laser cleaning, the magnet surface after laser cleaning prepares high knot
The high anti-corrosion protective coating of resultant force.
Preferably, elemental metals electrode material includes Cr, Mo, Cu, W or Co, multicomponent alloy electrode material in the step (1)
Material includes Cr-Ni-Ti, Mo-Cu-Al, Cr-Ni or Cu-Co.
Preferably, the parameter of laser cleaning technique includes laser power, pulse width, laser beam-wave in the step (2)
Long and incident angle and scanning speed, the laser power are 10~2000W, and laser pulse width is 20~220ns, laser beam
Wavelength is 1064nm, and laser incident angle is 30 °~90 °, and laser scanning speed is 10~100mm/s.
Preferably, the technological parameter of THE ELECTRIC SPARK STRENGTHENING TECHNIQUE includes discharge voltage, peak point current, arteries and veins in the step (3)
Width, pulse spacing and electrode movement speed are rushed, the discharge voltage of the Technology of Electric Spark Deposition is 30~150V, peak point current
For 2~30A, pulse width is 10~90 μ s, and the pulse spacing is 10~50 μ s, and electrode movement speed is 1~15mm/s.
Compared with prior art, the beneficial effects of the invention are as follows：
1, the present invention is surface-treated Sintered NdFeB magnet using laser cleaning technique, removes the oil of magnet surface
Dirty and oxide skin.Compared with traditional neodymium iron boron magnetic body surface alkali cleaning oil removing and acid pickling and rust removing, laser cleaning is a kind of environmentally protective
Cleaning way, be without the use of any chemical agent and cleaning solution, the waste material washed down is essentially all solid powder, body
Product is small, convenient for storage, recycling, can solve chemical cleaning bring problem of environmental pollution easily.Laser cleaning is high-efficient, saves
Time, have it is non-contact, without grinding, without fuel factor and be suitable for the cleaning characteristics such as various specifications magnet, magnet table can be removed
The various types of pollutants in face reach the cleannes routinely cleaned and be unable to reach.Therefore, using laser cleaning technique to neodymium iron boron
Magnet carries out pre-treatment, is able to solve the decline of table magnetic caused by pickling brought by current conventional magnet pre-treatment, part is cleaned
Object remains in matrix and problem of environmental pollution, it is considered to be substitute current Sintered NdFeB magnet surface pretreatment it is most reliable,
Most effective solution.
2, the present invention is the high energy pulse electric energy for utilizing moment using spark surface hardening technique, in electrode and matrix
High temperature, high-pressure area are formed between material, and electrode material is melted and is coated onto matrix surface, and formation meets physics, chemistry and machinery
The processing technique of performance requirement.Compared with conventional sintering neodymium iron boron magnetic body surfacecti proteon painting/coating, using THE ELECTRIC SPARK STRENGTHENING TECHNIQUE
The metallurgical bonding of the corrosion-inhibiting coating and matrix of preparation is very secured, will not peel off.And THE ELECTRIC SPARK STRENGTHENING TECHNIQUE is simply easily grasped
Make, electrode material range of choice is wide, is a kind of environmentally friendly magnet surface guard technology.Using THE ELECTRIC SPARK STRENGTHENING TECHNIQUE institute
The protective layer of preparation has the characteristics that excellent wearability, corrosion resistance and high-bond, can mention for Sintered NdFeB magnet
It is acted on for more lasting surfacecti proteon.
Specific embodiment
The technical scheme in the embodiments of the invention will be clearly and completely described below, it is clear that described implementation
Example is only a part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, this field is common
Technical staff's every other embodiment obtained without making creative work belongs to the model that the present invention protects
It encloses.
Embodiment 1
A kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning, includes the following steps：
(1) selection of electrode material：
Select simple substance Cr as the electrode material of THE ELECTRIC SPARK STRENGTHENING TECHNIQUE.
(2) laser cleaning：
Blocky Sintered NdFeB magnet (the state of the commercialization for selecting specification to be 32 × 18 × 4mm：It does not magnetize, the trade mark：38EH)
It is tested, Sintered NdFeB magnet is surface-treated using laser clear technique, remove greasy dirt and the oxidation of magnet surface
Skin, the laser power of laser cleaning are 10W, laser pulse width 20ns, a length of 1064nm of laser beam-wave, laser incident angle
It is 30 °, laser scanning speed 10mm/s.
(3) magnet surface intensive treatment：
Burning using THE ELECTRIC SPARK STRENGTHENING TECHNIQUE by the deposit electrode material in step (1) in step (2) after laser cleaning
Neodymium iron boron magnetic body surface is tied, the discharge voltage of the Technology of Electric Spark Deposition is 30V, and peak point current 2A, pulse width is 10 μ s, arteries and veins
10 μ s are divided between punching, electrode movement speed is 1mm/s.
Embodiment 2
A kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning, includes the following steps：
(1) selection of electrode material：
Select simple substance Co as the electrode material of THE ELECTRIC SPARK STRENGTHENING TECHNIQUE.
(2) laser cleaning：
Blocky Sintered NdFeB magnet (the state of the commercialization for selecting specification to be 32 × 18 × 4mm：It does not magnetize, the trade mark：38EH)
It is tested, Sintered NdFeB magnet is surface-treated using laser clear technique, remove greasy dirt and the oxidation of magnet surface
Skin, the laser power of laser cleaning are 1005W, laser pulse width 120ns, a length of 1064nm of laser beam-wave, laser light incident
Angle is 60 °, laser scanning speed 55mm/s.
(3) magnet surface intensive treatment：
Burning using THE ELECTRIC SPARK STRENGTHENING TECHNIQUE by the deposit electrode material in step (1) in step (2) after laser cleaning
Tie neodymium iron boron magnetic body surface.The discharge voltage of the Technology of Electric Spark Deposition is 90V, and peak point current 16A, pulse width is 50 μ s,
Pulse spacing is 30 μ s, and electrode movement speed is 8mm/s.
Embodiment 3
A kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning, includes the following steps：
(1) selection of electrode material：
Select multicomponent alloy Cr-Ni-Ti as the electrode material of THE ELECTRIC SPARK STRENGTHENING TECHNIQUE.
(2) laser cleaning：
Blocky Sintered NdFeB magnet (the state of the commercialization for selecting specification to be 32 × 18 × 4mm：It does not magnetize, the trade mark：38EH)
It is tested, Sintered NdFeB magnet is surface-treated using laser clear technique, remove greasy dirt and the oxidation of magnet surface
Skin.The laser power of laser cleaning is 2000W, laser pulse width 220ns, a length of 1064nm of laser beam-wave, laser light incident
Angle is 90 °, laser scanning speed 100mm/s.
(3) magnet surface intensive treatment：
Burning using THE ELECTRIC SPARK STRENGTHENING TECHNIQUE by the deposit electrode material in step (1) in step (2) after laser cleaning
Tie neodymium iron boron magnetic body surface.The discharge voltage of the Technology of Electric Spark Deposition is 150V, and peak point current 30A, pulse width is 90 μ s,
Pulse spacing is 50 μ s, and electrode movement speed is 15mm/s.
Comparative examples 1
To compare, this comparative examples is included the following steps using conventional Sintered NdFeB magnet plating mode：
(1) magnet pre-processes：
Alkali cleaning oil removing is carried out to Sintered NdFeB magnet respectively and acid pickling and rust removing is handled, wherein the temperature of degreasing fluid is 75
DEG C, pH value 12, the oil removing time is 15min, then handles 2min using the supersonic cleaning machine ultrasonic cleaning of 2000Hz；Using
The dust technology that mass fraction is 4wt% carries out acid pickling and rust removing to magnet, and pickling time 30s finally uses the ultrasound of 2000Hz
Cleaning machine ultrasonic cleaning handles 3min.
(2) preparation of electroless nickel layer：
Using depositing nickel coating on the Sintered NdFeB magnet surface of electroplating technology after the pre-treatment, electroplating technological parameter
For：PH value is 4.4, and temperature is 46 DEG C, current density 2.3A/dm2, electroplating time 50min.
Sample prepared by the sample and comparative examples 1 prepare to embodiment 1,2,3 carries out salt spray test (salt fog examination respectively
The condition tested is：Chamber temperature is 38 DEG C, and brine strength is 5% (volume ratio), using continuously spraying test method) and plating
Layer binding force is tested, and concrete outcome see the table below 1.
Table 1 is the sample salt spray resistance ability and binding force test result of embodiment 1,2,3 and comparative examples 1, test knot
Fruit is as follows：
| Sample | Salt spray test (h) | Binding force (MPa) |
| Embodiment 1 | 582 | 38.6 |
| Embodiment 2 | 490 | 40.5 |
| Embodiment 3 | 736 | 43.2 |
| Comparative examples 1 | 72 | 7.63 |
As it can be seen from table 1 compared with the sample of comparative examples 1, the salt spray resistance ability and knot of 1,2,3 sample of embodiment
Resultant force is significantly improved, and illustrates after carrying out pre-treatment to magnet using laser cleaning technique, then uses electrospark impregnation
The protective coating that technology is deposited in magnet surface can significantly improve the Corrosion Protection of magnet, and embodiment 3 is optimal side
Case.
It although an embodiment of the present invention has been shown and described, for the ordinary skill in the art, can be with
A variety of variations, modification, replacement can be carried out to these embodiments without departing from the principles and spirit of the present invention by understanding
And modification, the scope of the present invention is defined by the appended.
Claims (4)
1. a kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning, it is characterised in that：Including following
Step：
(1) selection of electrode material：Elemental metals or multicomponent alloy may be selected as electrode material；
(2) laser cleaning：Sintered NdFeB magnet is surface-treated using laser cleaning technique, removes the oil of magnet surface
Dirty and oxide skin；
(3) magnet surface intensive treatment：Using THE ELECTRIC SPARK STRENGTHENING TECHNIQUE, by the deposit electrode material selected in step (1) to step
Suddenly on the Sintered NdFeB magnet surface in (2) after laser cleaning, the magnet surface after laser cleaning prepares high-bond
High anti-corrosion protective coating.
2. a kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning according to claim 1,
It is characterized in that：Elemental metals electrode material includes Cr, Mo, Cu, W or Co, multicomponent alloy electrode material packet in the step (1)
Include Cr-Ni-Ti, Mo-Cu-Al, Cr-Ni or Cu-Co.
3. a kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning according to claim 1,
It is characterized in that：In the step (2) parameter of laser cleaning technique include laser power, pulse width, laser beam wavelength and
Incident angle and scanning speed, the laser power are 10~2000W, and laser pulse width is 20~220ns, laser beam wavelength
For 1064nm, laser incident angle is 30 °~90 °, and laser scanning speed is 10~100mm/s.
4. a kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning according to claim 1,
It is characterized in that：The technological parameter of THE ELECTRIC SPARK STRENGTHENING TECHNIQUE includes that discharge voltage, peak point current, pulse are wide in the step (3)
Degree, pulse spacing and electrode movement speed, the discharge voltage of the Technology of Electric Spark Deposition are 30~150V, peak point current 2
~30A, pulse width are 10~90 μ s, and the pulse spacing is 10~50 μ s, and electrode movement speed is 1~15mm/s.
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| CN201811060395.9A CN108866547A (en) | 2018-09-12 | 2018-09-12 | A kind of neodymium iron boron magnetic body electric spark on surface enhanced processing method based on laser cleaning |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109371397A (en) * | 2018-12-12 | 2019-02-22 | 常州大学 | A method of coating binding force is improved based on ultrasonic impact |
| CN112011754A (en) * | 2020-08-20 | 2020-12-01 | 合肥工业大学 | Preparation method of high-temperature-resistant samarium-cobalt permanent magnet |
| CN114717511A (en) * | 2022-03-30 | 2022-07-08 | 北矿磁材（阜阳）有限公司 | Preparation method of Al film on surface of sintered neodymium-iron-boron magnet |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1061925A (en) * | 1990-11-26 | 1992-06-17 | 北京市电加工研究所 | Pulse power supply for electric spark machine of conducting ceramic material |
| CN101768714A (en) * | 2010-02-09 | 2010-07-07 | 江苏大学 | Method for preparing thermal barrier coating by laser compound plasma spraying |
| JP2016149535A (en) * | 2015-02-12 | 2016-08-18 | 煙台首鋼磁性材料株式有限公司 | Nd-Fe-B SYSTEM PERMANENT MAGNET WITH COMPLEX COATING FILM AND MANUFACTURING METHOD OF COMPLEX COATING FILM OF Nd-Fe-B SYSTEM PERMANENT MAGNET SURFACE |
-
2018
- 2018-09-12 CN CN201811060395.9A patent/CN108866547A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1061925A (en) * | 1990-11-26 | 1992-06-17 | 北京市电加工研究所 | Pulse power supply for electric spark machine of conducting ceramic material |
| CN101768714A (en) * | 2010-02-09 | 2010-07-07 | 江苏大学 | Method for preparing thermal barrier coating by laser compound plasma spraying |
| JP2016149535A (en) * | 2015-02-12 | 2016-08-18 | 煙台首鋼磁性材料株式有限公司 | Nd-Fe-B SYSTEM PERMANENT MAGNET WITH COMPLEX COATING FILM AND MANUFACTURING METHOD OF COMPLEX COATING FILM OF Nd-Fe-B SYSTEM PERMANENT MAGNET SURFACE |
Non-Patent Citations (1)
| Title |
|---|
| 朱翠雯等: ""电火花加工NdFeB材料的表面性能"", 《中国表面工程》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109371397A (en) * | 2018-12-12 | 2019-02-22 | 常州大学 | A method of coating binding force is improved based on ultrasonic impact |
| CN112011754A (en) * | 2020-08-20 | 2020-12-01 | 合肥工业大学 | Preparation method of high-temperature-resistant samarium-cobalt permanent magnet |
| CN114717511A (en) * | 2022-03-30 | 2022-07-08 | 北矿磁材（阜阳）有限公司 | Preparation method of Al film on surface of sintered neodymium-iron-boron magnet |
| CN114717511B (en) * | 2022-03-30 | 2023-08-04 | 北矿磁材（阜阳）有限公司 | Preparation method of Al film on surface of sintered NdFeB magnet |
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Application publication date: 20181123 |