Vacuum aluminizing method of surface of neodymium-iron-boron permanent magnet

Abstract

The invention relates to a vacuum aluminizing method of the surface of a neodymium-iron-boron permanent magnet. The method sequentially comprises the following steps of: (1) polishing and cleaning the surface of the neodymium-iron-boron permanent magnet by adopting a wet method; (2) putting the neodymium-iron-boron permanent magnet on a rotating workpiece fame in a film plating chamber to ensure that the temperature of the neodymium-iron-boron permanent magnet is kept between 250 DEG C and 300 DEG C; (3) starting a vacuum pump on the film plating chamber and adjusting the vacuum degree of thefilm plating chamber to be 1-9*10<-3>Pa; (4) meanwhile, starting multi-arc cathode evaporators at both sides of the film plating chamber, a plane magnetic sputtering target and the rotating workpieceframe to carry out magnetic control multi-arc sputtering for 2-7 hours; (5) maintaining the film plating chamber to be cooled for 30-60 minutes under vacuum, aerating, opening the chamber, taking outthe aluminized neodymium-iron-boron permanent magnet and carrying out passivation with a non-chrome passivation solution. High energy ions generated by magnetron sputtering strike low-energy ions generated by the multi-arc method so as to promote the low-energy ions to generate more ionization, wherein the speeds and the trends of the high-energy ions and the low-energy ions are uniform, thus theefficiency is improved.

Description

technical field

[0001] The invention relates to a metal surface plating method with aluminum, in particular to a vacuum aluminum plating method on the surface of a neodymium-iron-boron permanent magnet. Background technique

[0002] The new permanent magnet material NdFeB is the third-generation rare earth material that appeared in 1983. Usually, NdFeB is composed of rich Nd and base phase Nd 2 Fe 14 Composed of phase B, in order to obtain excellent magnetic properties, this composite metallographic structure is necessary. However, it is this complex phase structure that is detrimental to the oxidation resistance of the magnet. The different phases in contact with each other form a "battery" due to the difference in electromotive force, the Nd-rich phase is the anode, and the base phase is the cathode. Nd is very easy to oxidize, and the rich Nd with a very small volume is accelerated to corrode under the action of a relatively large anodic current, and this corrosion pro...

Examples

Embodiment 1

[0024] A method for vacuum aluminum plating on the surface of an NdFeB permanent magnet, wherein the following steps are sequentially included:

[0025] (1) First, use wet polishing to treat the surface of NdFeB magnets with a size of 10×10×10mm. The weight ratio of each component in the abrasive is: 77.5 parts of water, 16.5 parts of glass beads, and 2.7 parts of sodium carbonate. The pressure is 0.2MPa, and the polishing angle is 45 degrees from the surface of the NdFeB permanent magnet;

[0026] (2) Put the NdFeB permanent magnet on the rotating workpiece rack in the coating chamber, start the vacuum pump on the coating chamber, and vacuum the coating chamber to a degree of 3×10 -2 Pa, and heated to keep the temperature of the NdFeB permanent magnet at 280°C;

[0027] (3) Start the vacuum pump on the coating chamber, when the vacuum chamber reaches the process design value of 10 -2 After Pa, carry out argon ion bombardment cleaning, which is a process of glow discharge, h...

Embodiment 2

[0032] A method for vacuum aluminum plating on the surface of an NdFeB permanent magnet, wherein the following steps are sequentially included:

[0033] (1) First use wet polishing to treat the surface of a NdFeB magnet with a size of 10×10×10mm. The weight ratio of each component in the abrasive is: 70 parts of water, 10 parts of glass beads, 0.5 parts of potassium sorbate, The working pressure is 0.1MPa, and the polishing angle is 30 degrees from the surface of the NdFeB permanent magnet;

[0034] (2) Put the NdFeB permanent magnet on the rotating workpiece rack in the coating chamber, start the vacuum pump on the coating chamber, and vacuum the coating chamber to a vacuum degree of 5×10 -2 Pa, and heated to keep the temperature of the NdFeB permanent magnet at 250 °C;

[0035] (3) Start the vacuum pump on the coating chamber, when the vacuum chamber reaches the process design value of 10 -2 After Pa, carry out argon ion bombardment cleaning, which is a process of glow dis...

Embodiment 3

[0040] A method for vacuum aluminum plating on the surface of an NdFeB permanent magnet, wherein the following steps are sequentially included:

[0041] (1) First, use wet polishing to treat the surface of the NdFeB magnet with a size of 10×10×10 mm. The weight ratio of each component in the abrasive is: 85 parts of water, 23 parts of glass beads, 5 parts of sodium phytate, The working pressure is 0.3MPa, and the polishing angle is 60 degrees from the surface of the NdFeB permanent magnet;

[0042] (2) Put the NdFeB permanent magnet on the rotating workpiece rack in the coating chamber, start the vacuum pump on the coating chamber, and vacuum the coating chamber to a vacuum degree of 8×10 -2 Pa, and heated to keep the temperature of the NdFeB permanent magnet at 300°C;

[0043] (3) Start the vacuum pump on the coating chamber, when the vacuum chamber reaches the process design value of 10 -2 After Pa, carry out argon ion bombardment cleaning, which is a process of glow disch...

technical field

[0001] The invention relates to a metal surface plating method with aluminum, in particular to a vacuum aluminum plating method on the surface of a neodymium-iron-boron permanent magnet. Background technique

[0002] The new permanent magnet material NdFeB is the third-generation rare earth material that appeared in 1983. Usually, NdFeB is composed of rich Nd and base phase Nd 2 Fe 14 Composed of phase B, in order to obtain excellent magnetic properties, this composite metallographic structure is necessary. However, it is this complex phase structure that is detrimental to the oxidation resistance of the magnet. The different phases in contact with each other form a "battery" due to the difference in electromotive force, the Nd-rich phase is the anode, and the base phase is the cathode. Nd is very easy to oxidize, and the rich Nd with a very small volume is accelerated to corrode under the action of a relatively large anodic current, and this corrosion pro...

Examples

Embodiment 1

[0024] A method for vacuum aluminum plating on the surface of an NdFeB permanent magnet, wherein the following steps are sequentially included:

[0025] (1) First, use wet polishing to treat the surface of NdFeB magnets with a size of 10×10×10mm. The weight ratio of each component in the abrasive is: 77.5 parts of water, 16.5 parts of glass beads, and 2.7 parts of sodium carbonate. The pressure is 0.2MPa, and the polishing angle is 45 degrees from the surface of the NdFeB permanent magnet;

[0026] (2) Put the NdFeB permanent magnet on the rotating workpiece rack in the coating chamber, start the vacuum pump on the coating chamber, and vacuum the coating chamber to a degree of 3×10 -2 Pa, and heated to keep the temperature of the NdFeB permanent magnet at 280°C;

[0027] (3) Start the vacuum pump on the coating chamber, when the vacuum chamber reaches the process design value of 10 -2 After Pa, carry out argon ion bombardment cleaning, which is a process of glow discharge, h...

Embodiment 2

[0032] A method for vacuum aluminum plating on the surface of an NdFeB permanent magnet, wherein the following steps are sequentially included:

[0033] (1) First use wet polishing to treat the surface of a NdFeB magnet with a size of 10×10×10mm. The weight ratio of each component in the abrasive is: 70 parts of water, 10 parts of glass beads, 0.5 parts of potassium sorbate, The working pressure is 0.1MPa, and the polishing angle is 30 degrees from the surface of the NdFeB permanent magnet;

[0034] (2) Put the NdFeB permanent magnet on the rotating workpiece rack in the coating chamber, start the vacuum pump on the coating chamber, and vacuum the coating chamber to a vacuum degree of 5×10 -2 Pa, and heated to keep the temperature of the NdFeB permanent magnet at 250 °C;

[0035] (3) Start the vacuum pump on the coating chamber, when the vacuum chamber reaches the process design value of 10 -2 After Pa, carry out argon ion bombardment cleaning, which is a process of glow dis...

Embodiment 3

[0040] A method for vacuum aluminum plating on the surface of an NdFeB permanent magnet, wherein the following steps are sequentially included:

[0041] (1) First, use wet polishing to treat the surface of the NdFeB magnet with a size of 10×10×10 mm. The weight ratio of each component in the abrasive is: 85 parts of water, 23 parts of glass beads, 5 parts of sodium phytate, The working pressure is 0.3MPa, and the polishing angle is 60 degrees from the surface of the NdFeB permanent magnet;

[0042] (2) Put the NdFeB permanent magnet on the rotating workpiece rack in the coating chamber, start the vacuum pump on the coating chamber, and vacuum the coating chamber to a vacuum degree of 8×10 -2 Pa, and heated to keep the temperature of the NdFeB permanent magnet at 300°C;

[0043] (3) Start the vacuum pump on the coating chamber, when the vacuum chamber reaches the process design value of 10 -2 After Pa, carry out argon ion bombardment cleaning, which is a process of glow disch...