Method for preparing anti-corrosion wear-resisting sintered Nd-Fe-B magnets

Abstract

The invention discloses a method for preparing anti-corrosion wear-resisting sintered Nd-Fe-B magnets. The method includes the following steps that first, sintered Nd-Fe-B magnet blanks are placed in an oil removing solution so that oil on the surfaces of the sintered Nd-Fe-B magnet blanks can be removed, and sand blasting and ultrasonic cleaning are performed on the sintered Nd-Fe-B magnet blanks; second, phosphating is performed on the sintered Nd-Fe-B magnet blanks; third, the products subjected to phosphating and bottoming are immersed into an electrophoresis solution to be subjected to cathode electrophoresis; fourth, primary water washing, spraying and secondary water washing are performed sequentially, and dehydration is performed; fifth, softening braking, curing baking and cooling are sequentially performed. Through the method for preparing the novel sintered Nd-Fe-B magnets, a surface cathode electrophoresis epoxy resin / nano-SiO2 composite coating subjected to phosphating and bottoming is prepared. The corrosion resistance and the wear resistance of the composite coating are greatly improved compared with a traditional epoxy resin coating, and the scratch resistance of the coating can also be correspondingly enhanced.

Description

technical field [0001] The invention relates to the field of surface treatment of sintered NdFeB permanent magnet materials, in particular to the preparation of an anti-corrosion and wear-resistant coating for sintered NdFeB magnets. Background technique [0002] Sintered Nd-Fe-B (Nd-Fe-B) permanent magnets (a typical representative of rare earth Nd-Fe-B permanent magnets) permanent magnets are currently the best permanent magnet materials, and have been widely used in many fields such as motors, automobiles, and wind power generation. . However, this type of magnet has an obvious disadvantage, that is, the magnet has poor corrosion resistance, which seriously affects the further application of NdFeB permanent magnet materials. At present, there are two main methods for anti-corrosion treatment of NdFeB magnets: one is to add Al, Co, Cu, Ga and other alloying elements to improve the corrosion resistance of the material matrix, and the other is to use metal coatings, organic...

AI Technical Summary

Problems solved by technology

However, after EP curing, the crosslinking density is high, showing a three-dimensional network structure, large internal stress, brittle texture, poor fatigue resistance, heat resistance, and impact resistance, as well as low peel strength, low cracking strain capacity, and poor heat and humidity resistance. and other shortcomings, coupled with high surface energy

Therefore, the epoxy resin coating prepared by cathodic electrophoresis on the surface of NdFeB magnetic materials has the disadvantages of high brittleness, poor impact resistance, and easy scratches.

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