Rare earth permanent magnet and its manufacturing method

Abstract

The present application relates to a method for preparing R-T-Q series rare earth permanent magnet alloys, which comprises the following steps: 1) preparing R-T-Q series rare earth alloys, melting the above alloys in a vacuum above 1400°C and quenching to produce Solidify the alloy, and then hydrogenate and crush the rapidly solidified alloy to obtain the first powder; 2) prepare a solidified metal containing at least one rare earth element, crush it to a size below 600 mesh, and obtain the second powder, and then mix it in a certain proportion Homogeneous; shape the uniformly mixed fine powder and heat it for 0.5-24 hours in the temperature range between 450℃-1200℃ for alloying treatment. Through this alloying treatment, a uniform distribution of rare earth-rich intergranular compounds is formed on the surface of the main phase, and by controlling the diffusion, the rare earth elements form a gradient distribution of concentration from high to low within the range of 1-300nm on the surface of the main phase; thus It plays the role of isolating the magnetic coupling and exchange between the main phases and the magnetic hardening of the surface of the main phase.

Description

technical field [0001] The present application relates to a raw material alloy for a rare earth magnet and a manufacturing method thereof. Background technique [0002] At present, there are two types of rare earth magnets, SmCo and R-T-Q, which have been widely used. The R-T-Q system is more widely used. [0003] R-T-Q series rare earth magnets are magnets with R2-T14-Q1 tetragonal structure crystal as the main phase. R is a rare earth element, T is a transition metal element, and Q is at least one element selected from B, C, N, P, Si, and Al. The rare earth element R is 10%-18% of the whole atomic ratio, the transition metal element T is 72%-85% of the whole atomic ratio, and the Q is 5%-10% of the whole atomic ratio. [0004] The widely used process method is powder metallurgy. The main technological process is: alloy smelting - powder making - pressing molding - sintering - tempering. [0005] The R-T-Q series rare earth magnet is mainly composed of the main phase R...

AI Technical Summary

Problems solved by technology

There is reduced remanence Br (at room temperature, such as the saturation magnetic polarization of Nd2-Fe14-B is about 1.6T, while the saturation magnetic polarization of Dy2-Fe14-B and Tb2-Fe14-B is only about 0.7T) and cannot fully The problem of using the grain boundary microstructure to increase the coercive force iHc

Therefore, it is not only impossible to produce R-T-Q rare earth magnets with high coercive force iHc and remanence Br, but also there is a problem of wasting precious and rare heavy rare earth element resources.