High-fluidity samarium-iron-nitrogen flexible bonded permanent magnet for injection molding and preparation method thereof

Abstract

The invention discloses a high-fluidity samarium-iron-nitrogen flexible bonded permanent magnet for injection molding and a preparation method thereof. The high-fluidity samarium-iron-nitrogen flexible bonded permanent magnet comprises the following components: 90-94 parts by weight of samarium-iron-nitrogen magnetic powder, 3-5 parts by weight of a rubber binder, 2-3 parts by weight of a plasticizer, 0.5-1 part by weight of a heat stabilizer and 0.5-1 part by weight of a lubricant. According to the invention, the samarium-iron-nitrogen flexible bonded permanent magnet meets the latest ROHS2.0standard certification standard, and has export and foreign exchange earning conditions; the injection-molded flexible samarium-iron-nitrogen magnet fills up the blank of a high-fluidity area of theinjection-molded flexible samarium-iron-nitrogen magnet, improves the upper limit of the use temperature of the current flexible bonded magnet from 80 DEG C to 120 DEG C, widens the use field, and improves the stability and reliability thereof.

Description

technical field [0001] The invention relates to the technical field of samarium-iron-nitrogen flexible bonded permanent magnets, in particular to a high-fluidity samarium-iron-nitrogen flexible bonded permanent magnet for injection molding and a preparation method thereof. Background technique [0002] SmFeN magnetic powder is an anisotropic rare earth magnetic powder used for bonded magnets. Due to its small particle size (about 1-2 microns), high magnetic powder performance and the characteristics of magnetic field orientation, it is especially suitable for injection molding. Bonded magnets. [0003] Injection-molded magnets need to have high melt fluidity to fill the mold and inject them into magnetic devices with complex shapes. At present, injection molding magnetic devices are divided into rigid magnets and flexible magnets from the form. The former has higher strength after molding and cooling, but it cannot be bent and deformed, so it is not suitable for deformation...

AI Technical Summary

Problems solved by technology

At present, injection molding magnetic devices are divided into rigid magnets and flexible magnets from the form. The former has higher strength after molding and cooling, but it cannot be bent and deformed, so it is not suitable for deformation assembly, such as micro-motors, sensors and other applications; the latter It can be bent and deformed after forming and cooling, and can be installed and used with complex firmware

[0004] At present, the existing patented technology in the aspect of injection molding bonded magnets shows that PPS or PA is used as the binder and mixed with samarium iron nitrogen magnetic powder for injection molding, and the shape of the molded product is rigid; there are few patent documents for injection molding of flexible samarium iron nitrogen magnetic powder It has been reported that due to the limitations of the formulation of the flexible injection molding bonded magnet, the plasticizer used is a diformate plasticizer containing a benzene ring structure, which does not meet the latest ROHS2.0 standard requirements, and its service temperature is lower than 80 degrees , which limits the use environment; the most important thing is that the melt fluidity of the material is low, less than 80g / 10min, which is not conducive to the full molding of devices with complex shapes

[0005] For example, the application number is "2011103338872" and the invention name is injection molding permanent magnet composite material containing polyphenylene sulfide and its preparation method. The patent uses polyphenylene sulfide and magnetic powder composed of neodymium iron boron, samarium iron nitrogen and ferrite The injection molding permanent magnet composite material is blended and injection molded by the system. The injection product is rigid and contains NdFeB, which belongs to rare earth. Neodymium is limited by rare earth resources and the price is relatively high.

[0006] For example, the application number is "201810730159" and the invention name is an environmentally friendly flexible magnet injection soft pellet and its preparation method and an environmentally friendly permanent magnetic ring for pneumatic devices made by using it. The patent does not clearly indicate that it contains samarium iron nitrogen magnetic powder; add The plastic component contains a benzene ring structure; the melt flow rate is less than 80g / 10min; the upper temperature resistance limit of the material is not clearly indicated

Images