CN109137004A - The method of Sintered NdFeB magnet electronickelling cupro-nickel - Google Patents
The method of Sintered NdFeB magnet electronickelling cupro-nickel Download PDFInfo
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- CN109137004A CN109137004A CN201811208555.XA CN201811208555A CN109137004A CN 109137004 A CN109137004 A CN 109137004A CN 201811208555 A CN201811208555 A CN 201811208555A CN 109137004 A CN109137004 A CN 109137004A
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- ndfeb magnet
- iron boron
- neodymium iron
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/10—Electroplating with more than one layer of the same or of different metals
- C25D5/12—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium
- C25D5/14—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium two or more layers being of nickel or chromium, e.g. duplex or triplex layers
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
- C25D3/12—Electroplating: Baths therefor from solutions of nickel or cobalt
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
- C25D3/38—Electroplating: Baths therefor from solutions of copper
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/18—Electroplating using modulated, pulsed or reversing current
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/34—Pretreatment of metallic surfaces to be electroplated
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D7/00—Electroplating characterised by the article coated
- C25D7/001—Magnets
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Abstract
The invention discloses a kind of methods of Sintered NdFeB magnet electronickelling cupro-nickel, including bottom Nickel Plating Treatment, copper plating treatment and surface layer Nickel Plating Treatment, bottom Nickel Plating Treatment the following steps are included: S1, in sulfate nickel solution using 43~51A initial surge current handle 6~10min of Sintered NdFeB magnet, then current reduction to 30~40A handle 60~80min, wherein, sulfate nickel solution are as follows: containing 345~380g/L nickel sulfate, 45~55g/L nickel chloride, 55~65g/L boric acid, 4ml/L additive aqueous solution, pH be 4~5；The temperature that Sintered NdFeB magnet is handled in sulfate nickel solution is 45~55 DEG C.The present invention can be obviously shortened the time of plating bottom nickle layer, reduce corrosion of the sulfate nickel solution to Sintered NdFeB magnet, enhance the binding force of bottom nickel layer and Sintered NdFeB magnet.
Description
Technical field
The present invention relates to sintered NdFeB electroplating technologies.It is more particularly related to a kind of sintered NdFeB
The method of magnet electronickelling cupro-nickel.
Background technique
With the development of rare-earth Nd-Fe-B permanent magnetic material, the problem of showing, increasingly shows in neodymium iron boron plating, from forming
For a key factor for restricting its development.Nd-Fe-B permanent magnet material belongs to powdered metallurgical material, and has potential difference difference larger
Multiphase composition, especially Nd-rich phase current potential is lower, easily generation intercrystalline corrosion.Therefore in order to improve the anti-corrosion of Sintered NdFeB magnet
Performance generallys use the plating mode of electrogalvanizing and electronickelling cupro-nickel.As end product automatic assembling is universal and product is long-lived
Life design, coating hardness, wear-resisting property, corrosion resistance and the binding force of cladding material of magnet product surface require more and more severe
It carves.Electronickelling cupro-nickel Nd-Fe-B permanent magnetic product carries out nickel plating generally in acidic Ni plating bath, but if plating time is longer,
Hydrogen ion and chloride ion in nickel plating solution can cause certain corrosion to neodymium iron boron magnetic body, and reduce coating and neodymium iron boron magnetic body
Binding force.
Summary of the invention
It is an object of the invention to solve at least the above problems, and provide the advantages of at least will be described later.
It is a still further object of the present invention to provide a kind of methods of Sintered NdFeB magnet electronickelling cupro-nickel, can be obvious
Shorten the time of plating bottom nickle layer, reduces corrosion of the sulfate nickel solution to Sintered NdFeB magnet, enhancing bottom nickel layer and sintering neodymium
The binding force of iron boron magnet.
In order to realize these purposes and other advantages according to the present invention, a kind of Sintered NdFeB magnet electronickelling is provided
The method of cupro-nickel, including bottom Nickel Plating Treatment, copper plating treatment and surface layer Nickel Plating Treatment, bottom Nickel Plating Treatment the following steps are included:
S1, in sulfate nickel solution using 43~51A initial surge current processing Sintered NdFeB magnet 6~
10min, then current reduction to 30~40A handles 60~80min, wherein sulfate nickel solution are as follows: the sulphur containing 345~380g/L
Sour nickel, 45~55g/L nickel chloride, 55~65g/L boric acid, 4ml/L additive aqueous solution, pH be 4~5.
Preferably, the temperature that Sintered NdFeB magnet is handled in sulfate nickel solution is 45~55 DEG C.
Preferably, bottom Nickel Plating Treatment further include: S2, sintered NdFeB are lived after handling in sulfate nickel solution
Change processing, be activated specifically: by Sintered NdFeB magnet concentration be 2~3mL/L sulfuric acid solution in impregnate 10~
20s。
Preferably, copper plating treatment the following steps are included:
A1, the electricity that bottom nickel plating treated Sintered NdFeB magnet is used to 20~30A in pyrophosphate copper solution
50~70min of stream process, temperature is 40~50 DEG C, and is washed, wherein pyrophosphate copper solution are as follows: the pyrophosphoric acid containing 45~65g/L
Copper, 270~330g/L potassium pyrophosphate, 2~4mL/L ammonium hydroxide, 2~4mL/L open cylinder agent aqueous solution, pH be 8.5~9.2；
10~20s is impregnated after A2, washing in the sulfuric acid solution that concentration is 4~5mL/L.
Preferably, the detailed process of surface layer Nickel Plating Treatment are as follows: by the Sintered NdFeB magnet after copper plating treatment in sulfuric acid
140~160min of current processing of 25~35A is used in salt nickel solution, wherein temperature is 45~55 DEG C, sulfate nickel solution
Are as follows: containing 240~300g/L nickel sulfate, 40~60g/L nickel chloride, 35~55g/L of boric acid, 2~4mL/L of additive aqueous solution,
PH is 3.8~4.5.
Preferably, processing, the detailed process of pre-treatment before Sintered NdFeB magnet carries out before bottom Nickel Plating Treatment
Are as follows:
B1, Sintered NdFeB magnet is subjected to grinding chamfering, obtains pretreatment neodymium iron boron magnetic body；
B2, neodymium iron boron magnetic body progress ultrasonic degreasing oil removing, time 90 will be pre-processed under the conditions of temperature is 50~60 DEG C
~120s obtains degreasing sintered neodymium iron boron magnetic body；
B3, the nitric acid solution 40~80s of pickling for being 4~5% by degreasing sintered neodymium iron boron magnetic body concentration, and wash, so
Sintered NdFeB magnet is directly poured into afterwards and carries out 40~70s of ultrasonic cleaning in ultrasonic wave, obtains ultrasonic cleaning sintered NdFeB
Wherein, ultrasonic power is 1~2kW to magnetic；
B4, Sintered NdFeB magnet will be cleaned by ultrasonic according to operation reprocessing 3~5 times of B3, and will obtain cleaning neodymium iron boron
Magnet；
B5, hydrofluoric acid solution 50~60s of immersion that neodymium iron boron magnetic body concentration is 1~2% will be cleaned, and washed, obtained
Sintered NdFeB magnet for bottom Nickel Plating Treatment.
Preferably, sealing pores are carried out before carrying out pretreatment procedure to Sintered NdFeB magnet, sealing pores
Detailed process are as follows:
C1, under inert gas protection, the poly- silicon oxygen of zinc stearate, methyl aminopropyl for being 20:8:1:1:5 by mass ratio
Alkane, sorbierite, polyvinylpyrrolidone and phytic acid are mixed be incorporated in 150~160 DEG C under the conditions of to be heated to system be molten mass,
Then it is cooled to 100~110 DEG C under inert gas protection, obtains hole sealing agent, wherein amino in methyl aminopropylpolysiloxane
Content be 12%~15%, molecular weight be 4000~6000；
Sintered NdFeB magnet is rinsed 5~10min by C2, under inert gas protection in circulating water, naturally dry,
Then 2~3min is heated under the conditions of 100~150 DEG C, obtains thermal sintering neodymium iron boron magnetic body；
C3, hot neodymium iron boron magnetic body impregnated into hole sealing agent 5~10min, and naturally dry under inert gas protection, obtained
To processing neodymium iron boron magnetic body, 10~20s is freezed under the conditions of processing neodymium iron boron magnetic body is then placed in -10~0 DEG C, obtains freezing neodymium
Then freezing neodymium iron boron magnetic body is solidified under the conditions of 80~90 DEG C 5~10min, obtains the burning operated for B1 by iron boron magnet
Tie neodymium iron boron magnetic body.
The present invention is include at least the following beneficial effects:
The first, the present invention effectively shortens sintering neodymium by the concentration and initial surge current intensity for improving nickel sulfate
The time of iron boron magnet plating bottom nickle layer reduces sulfate nickel solution to the anticaustic of Sintered NdFeB magnet, improves sintering
The binding force of neodymium iron boron magnetic body and bottom nickel layer, while by the control plating bottom nickle time, it realizes the control to bottom nickel layer thickness, reduces
Binding force of the stress of bottom nickel layer to Sintered NdFeB magnet.
The second, it is directly fallen in pretreatment process by multiple pickling and ultrasonic cleaning and by Sintered NdFeB magnet
Entering cleaning in supersonic wave cleaning machine, the shield effectiveness bring that this operation avoids pickling tooling influences, meanwhile, using dilute hydrogen
Fluorspar acid solution, which is activated, not only removes the oxide layer of product surface, but also it is attached newly to form a large amount of acid-leached product
In Sintered NdFeB magnet surface, it ensure that the sintering ferromagnetic cleannes of neodymium, and then improve Sintered NdFeB magnet and bottom
The binding force of nickel layer.
Third, by zinc stearate be added methyl aminopropylpolysiloxane, sorbierite, polyvinylpyrrolidone, with
And phytic acid can be improved the binding force of zinc stearate and Sintered NdFeB magnet, avoid the tristearin in Sintered NdFeB magnet hole
Sour zinc falls off, and improves the corrosion resistance of Sintered NdFeB magnet, and then improve the combination of Sintered NdFeB magnet and bottom nickel layer
Power；Methyl aminopropylpolysiloxane, phytic acid reduce corrosion of the acid solution to Sintered NdFeB magnet.
4th, neodymium iron boron magnetic body is first processed into thermal sintering neodymium iron boron magnetic body, is then place by the processing of hot neodymium iron boron magnetic body
Neodymium iron boron magnetic body is managed, then processing neodymium-iron-boron is processed into freezing neodymium iron boron magnetic body, will finally be freezed at neodymium iron boron magnetic body solidification
Reason, this operation can make zinc stearate is more uniform to be filled in the hole of Sintered NdFeB magnet, improve sintering neodymium iron
The corrosion resistance of boron magnet.
Further advantage, target and feature of the invention will be partially reflected by the following instructions, and part will also be by this
The research and practice of invention and be understood by the person skilled in the art.
Specific embodiment
The present invention will be further described in detail below with reference to the embodiments, to enable those skilled in the art referring to specification
Text can be implemented accordingly.
<embodiment 1>
At the method for Sintered NdFeB magnet electronickelling cupro-nickel, including bottom Nickel Plating Treatment, copper plating treatment and surface layer nickel plating
Reason, bottom Nickel Plating Treatment the following steps are included:
S1, the initial surge current of 43A is used to handle Sintered NdFeB magnet 6min in sulfate nickel solution, it is then electric
Stream is reduced to 30A to handle 60min, wherein sulfate nickel solution are as follows: nickel sulfate containing 345g/L, 45g/L nickel chloride, 55g/L boron
The aqueous solution of acid, 2ml/L additive, pH 4.
The temperature that Sintered NdFeB magnet is handled in sulfate nickel solution is 45 DEG C.
Bottom Nickel Plating Treatment further include: S2, sintered NdFeB are activated after handling in sulfate nickel solution, living
Change processing specifically: Sintered NdFeB magnet is impregnated into 10s in the sulfuric acid solution that concentration is 2mL/L.
Copper plating treatment the following steps are included:
A1, by bottom nickel plating treated Sintered NdFeB magnet in pyrophosphate copper solution using the electric current of 20A at
50min is managed, temperature is 40 DEG C, and is washed, wherein pyrophosphate copper solution are as follows: cupric pyrophosphate containing 45g/L, 270g/L pyrophosphoric acid
Potassium, 2mL/L ammonium hydroxide, 2mL/L open cylinder agent aqueous solution, pH 8.5；
10s is impregnated in the sulfuric acid solution that concentration is 4mL/L after A2, washing.
The detailed process of surface layer Nickel Plating Treatment are as follows: by the Sintered NdFeB magnet after copper plating treatment in sulfate nickel solution
Use the current processing 140min of 25A, wherein temperature is 45 DEG C, sulfate nickel solution are as follows: nickel sulfate containing 240g/L, 40g/L chlorine
Change the aqueous solution of nickel, boric acid 35g/L, additive 2mL/L, pH 3.8.
Processing before Sintered NdFeB magnet carries out before bottom Nickel Plating Treatment, the detailed process of pre-treatment are as follows:
B1, Sintered NdFeB magnet is subjected to grinding chamfering, obtains pretreatment neodymium iron boron magnetic body；
B2, neodymium iron boron magnetic body progress ultrasonic degreasing oil removing will be pre-processed under the conditions of temperature is 50 DEG C, time 90s is obtained
To degreasing sintered neodymium iron boron magnetic body；
B3, the nitric acid solution pickling 40s for being 4% by degreasing sintered neodymium iron boron magnetic body concentration, and wash, it then will sintering
Neodymium iron boron magnetic body, which directly pours into, carries out ultrasonic cleaning 40s in ultrasonic wave, obtain ultrasonic cleaning sintered NdFeB magnetic wherein, ultrasonic wave
Power is 1kW；
B4, Sintered NdFeB magnet will be cleaned by ultrasonic according to operation reprocessing 3 times of B3, and will obtain cleaning neodymium-iron-boron
Body；
B5, the hydrofluoric acid solution immersion 50s that neodymium iron boron magnetic body concentration is 1% will be cleaned, and washed, obtained for bottom
The Sintered NdFeB magnet of Nickel Plating Treatment.
Wherein, additive is specially allyl sulfonamide, and open cylinder agent includes mantoquita, phosphoric acid, potassium dihydrogen phosphate, Yi Jishui,
It is 3 μm by the average thickness of bottom layer nickel derived above, the average thickness of copper plate is 1 μm, and the average thickness of surface layer nickel is 4 μ
M, the data that thickness is tested by X-ray thickness gauge, methyl aminopropylpolysiloxane are N, N- dimethyl aminopropyl ammonia third
Base dimethyl silicone polymer.
<embodiment 2>
At the method for Sintered NdFeB magnet electronickelling cupro-nickel, including bottom Nickel Plating Treatment, copper plating treatment and surface layer nickel plating
Reason, bottom Nickel Plating Treatment the following steps are included:
S1, the initial surge current of 47A is used to handle Sintered NdFeB magnet 8min in sulfate nickel solution, it is then electric
Stream is reduced to 35A to handle 70min, wherein sulfate nickel solution are as follows: nickel sulfate containing 365g/L, 50g/L nickel chloride, 50g/L boron
The aqueous solution of acid, 3ml/L additive, pH 4.5.
The temperature that Sintered NdFeB magnet is handled in sulfate nickel solution is 50 DEG C.
Bottom Nickel Plating Treatment further include: S2, sintered NdFeB are activated after handling in sulfate nickel solution, living
Change processing specifically: Sintered NdFeB magnet is impregnated into 15s in the sulfuric acid solution that concentration is 2.5mL/L.
Copper plating treatment the following steps are included:
A1, the electricity that bottom nickel plating treated Sintered NdFeB magnet is used to 20~30A in pyrophosphate copper solution
Stream process 60min, temperature is 40~50 DEG C, and is washed, wherein pyrophosphate copper solution are as follows: cupric pyrophosphate containing 55g/L, 300g/
L potassium pyrophosphate, 3mL/L ammonium hydroxide, 3mL/L open cylinder agent aqueous solution, pH 8.8；
15s is impregnated in the sulfuric acid solution that concentration is 4.5mL/L after A2, washing.
The detailed process of surface layer Nickel Plating Treatment are as follows: by the Sintered NdFeB magnet after copper plating treatment in sulfate nickel solution
Use the current processing 150min of 30A, wherein temperature is 50 DEG C, sulfate nickel solution are as follows: nickel sulfate containing 270g/L, 50g/L chlorine
Change the aqueous solution of nickel, boric acid 45g/L, additive 3mL/L, pH 4.1.
Processing before Sintered NdFeB magnet carries out before bottom Nickel Plating Treatment, the detailed process of pre-treatment are as follows:
B1, Sintered NdFeB magnet is subjected to grinding chamfering, obtains pretreatment neodymium iron boron magnetic body；
B2, neodymium iron boron magnetic body progress ultrasonic degreasing oil removing will be pre-processed under the conditions of temperature is 55 DEG C, time 105s is obtained
To degreasing sintered neodymium iron boron magnetic body；
B3, the nitric acid solution pickling 60s for being 4.5% by degreasing sintered neodymium iron boron magnetic body concentration, and wash, then it will burn
Knot neodymium iron boron magnetic body, which directly pours into, carries out ultrasonic cleaning 55s in ultrasonic wave, obtain ultrasonic cleaning sintered NdFeB magnetic wherein, ultrasound
Wave power is 1kW；
B4, Sintered NdFeB magnet will be cleaned by ultrasonic according to operation reprocessing 4 times of B3, and will obtain cleaning neodymium-iron-boron
Body；
B5, the hydrofluoric acid solution immersion 55s that neodymium iron boron magnetic body concentration is 1.5% will be cleaned, and washed, obtained the bottom of for
The Sintered NdFeB magnet of layer Nickel Plating Treatment.
Wherein, additive is specially allyl sulfonamide, and open cylinder agent includes mantoquita, phosphoric acid, potassium dihydrogen phosphate, Yi Jishui,
It is 4 μm by the average thickness of bottom layer nickel derived above, the average thickness of copper plate is 2 μm, and the average thickness of surface layer nickel is 6 μ
M, the data that thickness is tested by X-ray thickness gauge, methyl aminopropylpolysiloxane are N, N- dimethyl aminopropyl ammonia third
Base dimethyl silicone polymer.
<embodiment 3>
At the method for Sintered NdFeB magnet electronickelling cupro-nickel, including bottom Nickel Plating Treatment, copper plating treatment and surface layer nickel plating
Reason, bottom Nickel Plating Treatment the following steps are included:
S1, the initial surge current of 51A is used to handle Sintered NdFeB magnet 10min in sulfate nickel solution, then
Current reduction to 40A handle 80min, wherein sulfate nickel solution are as follows: nickel sulfate containing 380g/L, 55g/L nickel chloride, 65g/L boron
The aqueous solution of acid, 4ml/L additive, pH 5.
The temperature that Sintered NdFeB magnet is handled in sulfate nickel solution is 55 DEG C.
Bottom Nickel Plating Treatment further include: S2, sintered NdFeB are activated after handling in sulfate nickel solution, living
Change processing specifically: Sintered NdFeB magnet is impregnated into 20s in the sulfuric acid solution that concentration is 3mL/L.
Copper plating treatment the following steps are included:
A1, by bottom nickel plating treated Sintered NdFeB magnet in pyrophosphate copper solution using the electric current of 30A at
70min is managed, temperature is 50 DEG C, and is washed, wherein pyrophosphate copper solution are as follows: cupric pyrophosphate containing 65g/L, 330g/L pyrophosphoric acid
Potassium, 4mL/L ammonium hydroxide, 4mL/L open cylinder agent aqueous solution, pH 9.2；
20s is impregnated in the sulfuric acid solution that concentration is 5mL/L after A2, washing.
The detailed process of surface layer Nickel Plating Treatment are as follows: by the Sintered NdFeB magnet after copper plating treatment in sulfate nickel solution
Use the current processing 160min of 35A, wherein temperature is 55 DEG C, sulfate nickel solution are as follows: nickel sulfate containing 300g/L, 60g/L chlorine
Change the aqueous solution of nickel, boric acid 55g/L, additive 4mL/L, pH 4.5.
Processing before Sintered NdFeB magnet carries out before bottom Nickel Plating Treatment, the detailed process of pre-treatment are as follows:
B1, Sintered NdFeB magnet is subjected to grinding chamfering, obtains pretreatment neodymium iron boron magnetic body；
B2, neodymium iron boron magnetic body progress ultrasonic degreasing oil removing will be pre-processed under the conditions of temperature is 60 DEG C, time 120s is obtained
To degreasing sintered neodymium iron boron magnetic body；
B3, the nitric acid solution pickling 80s for being 5% by degreasing sintered neodymium iron boron magnetic body concentration, and wash, it then will sintering
Neodymium iron boron magnetic body, which directly pours into, carries out ultrasonic cleaning 70s in ultrasonic wave, obtain ultrasonic cleaning sintered NdFeB magnetic wherein, ultrasonic wave
Power is 2kW；
B4, Sintered NdFeB magnet will be cleaned by ultrasonic according to operation reprocessing 5 times of B3, and will obtain cleaning neodymium-iron-boron
Body；
B5, the hydrofluoric acid solution immersion 60s that neodymium iron boron magnetic body concentration is 2% will be cleaned, and washed, obtained for bottom
The Sintered NdFeB magnet of Nickel Plating Treatment.
Wherein, additive is specially allyl sulfonamide, and open cylinder agent includes mantoquita, phosphoric acid, potassium dihydrogen phosphate, Yi Jishui,
It is 5 μm by the average thickness of bottom layer nickel derived above, the average thickness of copper plate is 3 μm, and the average thickness of surface layer nickel is 6 μ
M, the data that thickness is tested by X-ray thickness gauge, methyl aminopropylpolysiloxane are N, N- dimethyl aminopropyl ammonia third
Base dimethyl silicone polymer.
<embodiment 4>
At the method for Sintered NdFeB magnet electronickelling cupro-nickel, including bottom Nickel Plating Treatment, copper plating treatment and surface layer nickel plating
Reason, bottom Nickel Plating Treatment the following steps are included:
S1, the initial surge current of 51A is used to handle Sintered NdFeB magnet 10min in sulfate nickel solution, then
Current reduction to 40A handle 80min, wherein sulfate nickel solution are as follows: nickel sulfate containing 380g/L, 55g/L nickel chloride, 65g/L boron
The aqueous solution of acid, 4ml/L additive, pH 5.
The temperature that Sintered NdFeB magnet is handled in sulfate nickel solution is 55 DEG C.
Bottom Nickel Plating Treatment further include: S2, sintered NdFeB are activated after handling in sulfate nickel solution, living
Change processing specifically: Sintered NdFeB magnet is impregnated into 20s in the sulfuric acid solution that concentration is 3mL/L.
Copper plating treatment the following steps are included:
A1, by bottom nickel plating treated Sintered NdFeB magnet in pyrophosphate copper solution using the electric current of 30A at
70min is managed, temperature is 50 DEG C, and is washed, wherein pyrophosphate copper solution are as follows: cupric pyrophosphate containing 65g/L, 330g/L pyrophosphoric acid
Potassium, 4mL/L ammonium hydroxide, 4mL/L open cylinder agent aqueous solution, pH 9.2；
20s is impregnated in the sulfuric acid solution that concentration is 5mL/L after A2, washing.
The detailed process of surface layer Nickel Plating Treatment are as follows: by the Sintered NdFeB magnet after copper plating treatment in sulfate nickel solution
Use the current processing 160min of 35A, wherein temperature is 55 DEG C, sulfate nickel solution are as follows: nickel sulfate containing 300g/L, 60g/L chlorine
Change the aqueous solution of nickel, boric acid 55g/L, additive 4mL/L, pH 4.5.
Processing before Sintered NdFeB magnet carries out before bottom Nickel Plating Treatment, the detailed process of pre-treatment are as follows:
B1, Sintered NdFeB magnet is subjected to grinding chamfering, obtains pretreatment neodymium iron boron magnetic body；
B2, neodymium iron boron magnetic body progress ultrasonic degreasing oil removing will be pre-processed under the conditions of temperature is 60 DEG C, time 120s is obtained
To degreasing sintered neodymium iron boron magnetic body；
B3, the nitric acid solution pickling 80s for being 5% by degreasing sintered neodymium iron boron magnetic body concentration, and wash, it then will sintering
Neodymium iron boron magnetic body, which directly pours into, carries out ultrasonic cleaning 70s in ultrasonic wave, obtain ultrasonic cleaning sintered NdFeB magnetic wherein, ultrasonic wave
Power is 2kW；
B4, Sintered NdFeB magnet will be cleaned by ultrasonic according to operation reprocessing 5 times of B3, and will obtain cleaning neodymium-iron-boron
Body；
B5, the hydrofluoric acid solution immersion reason 60s that neodymium iron boron magnetic body concentration is 2% will be cleaned, and washed, obtained the bottom of for
The Sintered NdFeB magnet of layer Nickel Plating Treatment.
Sealing pores, the detailed process of sealing pores are carried out before carrying out pretreatment procedure to Sintered NdFeB magnet
Are as follows:
C1, under inert gas protection, the poly- silicon oxygen of zinc stearate, methyl aminopropyl for being 20:8:1:1:5 by mass ratio
Alkane, sorbierite, polyvinylpyrrolidone and phytic acid are mixed be incorporated in 160 DEG C under the conditions of to be heated to system be molten mass, then exist
It is cooled to 110 DEG C under inert gas shielding, obtains hole sealing agent, wherein the content of amino is in methyl aminopropylpolysiloxane
15%, molecular weight 5000；
Sintered NdFeB magnet is rinsed 10min by C2, under inert gas protection in circulating water, naturally dry, then
3min is heated under the conditions of 150 DEG C, obtains thermal sintering neodymium iron boron magnetic body；
C3, hot neodymium iron boron magnetic body impregnated into hole sealing agent 10min, and naturally dry under inert gas protection, obtained
Neodymium iron boron magnetic body is handled, then processing neodymium iron boron magnetic body is placed under the conditions of 0 DEG C and freezes 20s, obtains freezing neodymium iron boron magnetic body, so
Freezing neodymium iron boron magnetic body is solidified into 10min under the conditions of 90 DEG C afterwards, obtains the Sintered NdFeB magnet operated for B1.
Wherein, additive is specially allyl sulfonamide, and open cylinder agent includes mantoquita, phosphoric acid, potassium dihydrogen phosphate, Yi Jishui,
It is 5 μm by the average thickness of bottom layer nickel derived above, the average thickness of copper plate is 3 μm, and the average thickness of surface layer nickel is 6 μ
M, the data that thickness is tested by X-ray thickness gauge, methyl aminopropylpolysiloxane are N, N- dimethyl aminopropyl ammonia third
Base dimethyl silicone polymer.
<comparative example 1>
Bottom Nickel Plating Treatment, copper plating treatment and surface layer Nickel Plating Treatment conventionally are carried out to Sintered NdFeB magnet.
<comparative example 2>
The method of Sintered NdFeB magnet electronickelling cupro-nickel is the same as embodiment 3, wherein the difference is that in bottom Nickel Plating Treatment
It is handled using the nickel sulfate solution and conventional current of conventional sulfuric acid nickel content.
<comparative example 3>
The method of Sintered NdFeB magnet electronickelling cupro-nickel is the same as embodiment 3, wherein the difference is that pre-treatment is using routine
Method is handled.
<performance test>
The Sintered NdFeB magnet that embodiment 3, embodiment 4, comparative example 1, comparative example 2, comparative example 3 are obtained corresponds
It is bonded in loudspeaker U shell and washer piece surface and carries out fall-down test, record falling height and drop number when coating falls off, as a result
It is as shown in table 1:
Table 1 falls data
Interpretation of result:
1, comparative example 3, comparative example 1 and comparative example 2 fall data it is found that embodiment 3 load-bearing be only be self-possessed
When, falling height 1.7 and drop number 105 are all larger than comparative example 1, comparative example 2 falls data, meanwhile, embodiment 3 increase from
After weighing 75% counterweight, falling height 1.8 and drop number 122 are still significantly greater than comparative example 1, comparative example 2, this just illustrates logical
The thickness crossed and improve the concentration of nickel sulfate, improve initial surge current intensity and control plating bottom nickle can effectively enhance sintering
The binding force of neodymium iron boron magnetic body and bottom nickel layer.
2, comparative example 3, comparative example 1 and comparative example 3 fall data it is found that embodiment 3 load-bearing be only be self-possessed
When, falling height 1.7 and drop number 105 are all larger than comparative example 1, comparative example 3 falls data, meanwhile, embodiment 3 increase from
After weighing 75% counterweight, falling height 1.8 and drop number 122 are still significantly greater than comparative example 1, comparative example 3, this just illustrates logical
Sintered NdFeB magnet and bottom nickel layer can effectively be enhanced to Sintered NdFeB magnet progress pre-treatment by crossing method of the invention
Binding force.
3, comparative example 3 and implement 4 and fall data it is found that embodiment 4 and embodiment 4 are when load-bearing is only to be self-possessed,
The falling height 1.8 and drop number 150 of embodiment 4 are all larger than the data of falling of embodiment 3, meanwhile, embodiment 3 and embodiment
After 4 increase the counterweight of self weight 75%, the falling height 2.1 and drop number 169 of embodiment 4 are still significantly greater than embodiment 3
Fall data, this carries out sealing pores to sintered NdFeB using method of the invention with regard to explanation, can be improved raising sintering neodymium
The corrosion resistance of iron boron magnet, and then improve the binding force of Sintered NdFeB magnet and bottom nickel layer.
Although the embodiments of the present invention have been disclosed as above, but its is not only in the description and the implementation listed
With it can be fully applied to various fields suitable for the present invention, for those skilled in the art, can be easily
Realize other modification, therefore without departing from the general concept defined in the claims and the equivalent scope, the present invention is simultaneously unlimited
In specific details and embodiment shown and described herein.
Claims (7)
1. at the method for Sintered NdFeB magnet electronickelling cupro-nickel, including bottom Nickel Plating Treatment, copper plating treatment and surface layer nickel plating
Reason, which is characterized in that bottom Nickel Plating Treatment the following steps are included:
S1, the initial surge current of 43~51A is used to handle 6~10min of Sintered NdFeB magnet in sulfate nickel solution, so
Afterwards current reduction to 30~40A handle 60~80min, wherein sulfate nickel solution are as follows: containing 345~380g/L nickel sulfate, 45~
55g/L nickel chloride, 55~65g/L boric acid, 4ml/L additive aqueous solution, pH be 4~5.
2. the method for Sintered NdFeB magnet electronickelling cupro-nickel as described in claim 1, which is characterized in that molten in sulfate nickel
The temperature that Sintered NdFeB magnet is handled in liquid is 45~55 DEG C.
3. the method for Sintered NdFeB magnet electronickelling cupro-nickel as described in claim 1, which is characterized in that bottom Nickel Plating Treatment
Further include: S2, sintered NdFeB are activated after handling in sulfate nickel solution, are activated specifically: will be sintered
Neodymium iron boron magnetic body impregnates 10~20s in the sulfuric acid solution that concentration is 2~3mL/L.
4. the method for Sintered NdFeB magnet electronickelling cupro-nickel as described in claim 1, which is characterized in that copper plating treatment includes
Following steps:
A1, by bottom nickel plating treated Sintered NdFeB magnet in pyrophosphate copper solution using the electric current of 20~30A at
Manage 50~70min, temperature is 40~50 DEG C, and is washed, wherein pyrophosphate copper solution are as follows: containing 45~65g/L cupric pyrophosphate,
270~330g/L potassium pyrophosphate, 2~4mL/L ammonium hydroxide, 2~4mL/L open cylinder agent aqueous solution, pH be 8.5~9.2；
10~20s is impregnated after A2, washing in the sulfuric acid solution that concentration is 4~5mL/L.
5. the method for Sintered NdFeB magnet electronickelling cupro-nickel as described in claim 1, which is characterized in that surface layer Nickel Plating Treatment
Detailed process are as follows: by the Sintered NdFeB magnet after copper plating treatment in sulfate nickel solution using 25~35A electric current at
Manage 140~160min, wherein temperature is 45~55 DEG C, sulfate nickel solution are as follows: contains 240~300g/L nickel sulfate, 40~60g/
The aqueous solution of L nickel chloride, 35~55g/L of boric acid, 2~4mL/L of additive, pH are 3.8~4.5.
6. the method for Sintered NdFeB magnet electronickelling cupro-nickel as described in claim 1, which is characterized in that sintered NdFeB magnetic
Processing before body carries out before bottom Nickel Plating Treatment, the detailed process of pre-treatment are as follows:
B1, Sintered NdFeB magnet is subjected to grinding chamfering, obtains pretreatment neodymium iron boron magnetic body；
B2, temperature be 50~60 DEG C under the conditions of will pretreatment neodymium iron boron magnetic body carry out ultrasonic degreasing oil removing, the time be 90~
120s obtains degreasing sintered neodymium iron boron magnetic body；
B3, the nitric acid solution 40~80s of pickling for being 4~5% by degreasing sintered neodymium iron boron magnetic body concentration, and wash, then will
Sintered NdFeB magnet, which directly pours into, carries out 40~70s of ultrasonic cleaning in ultrasonic wave, obtain ultrasonic cleaning sintered NdFeB magnetic its
In, ultrasonic power is 1~2kW；
B4, Sintered NdFeB magnet will be cleaned by ultrasonic according to operation reprocessing 3~5 times of B3, and will obtain cleaning neodymium iron boron magnetic body；
B5, hydrofluoric acid solution 50~60s of immersion that neodymium iron boron magnetic body concentration is 1~2% will be cleaned, and washed, will be used for
The Sintered NdFeB magnet of bottom Nickel Plating Treatment.
7. the method for Sintered NdFeB magnet electronickelling cupro-nickel as claimed in claim 6, which is characterized in that sintering neodymium iron
Boron magnet carries out carrying out sealing pores, the detailed process of sealing pores before pretreatment procedure are as follows:
C1, under inert gas protection, zinc stearate, the methyl aminopropylpolysiloxane, mountain for being 20:8:1:1:5 by mass ratio
Pears alcohol, polyvinylpyrrolidone and phytic acid are mixed be incorporated in 150~160 DEG C under the conditions of to be heated to system be molten mass, then exist
It is cooled to 100~110 DEG C under inert gas shielding, obtains hole sealing agent, wherein the content of amino in methyl aminopropylpolysiloxane
It is 12%~15%, molecular weight is 4000~6000；
Sintered NdFeB magnet is rinsed 5~10min by C2, under inert gas protection in circulating water, naturally dry, then
2~3min is heated under the conditions of 100~150 DEG C, obtains thermal sintering neodymium iron boron magnetic body；
C3, hot neodymium iron boron magnetic body impregnated into hole sealing agent 5~10min, and naturally dry under inert gas protection, obtained everywhere
Neodymium iron boron magnetic body is managed, freezes 10~20s under the conditions of processing neodymium iron boron magnetic body is then placed in -10~0 DEG C, obtains freezing neodymium iron boron
Then freezing neodymium iron boron magnetic body is solidified under the conditions of 80~90 DEG C 5~10min, obtains the sintering neodymium operated for B1 by magnet
Iron boron magnet.
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| CN111304707A (en) * | 2020-04-03 | 2020-06-19 | 包头汇众磁谷稀土科技有限公司 | Neodymium iron boron permanent magnet material surface copper plating solution and surface treatment method thereof |
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| CN113088970A (en) * | 2021-03-30 | 2021-07-09 | 广东小天才科技有限公司 | Magnet with phosphorus-nickel coating and preparation method thereof |
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