NdFeB合金选择氢爆的研究

Study on Selective Hydrogen Decrepitation of NdFeB Alloys

对NdFeB合金的选择氢爆进行了研究。研究表明,在较低的环境温度和氢气压力下,通过事先对合金中富Nd相的吸氢量进行理论计算并对放入容器内的NdFeB合金量进行定量控制,NdFeB合金在吸氢过程中完全可以实现良好的选择氢爆。SEM观察表明,选择氢爆时其碎裂的方式均为沿晶断裂,爆裂后粉末中的主相晶粒均是单晶粒子,Nd2Fe14B主相晶粒内均无裂纹形成。与完全氢爆相比,选择氢爆后的晶粒较粗大,且较均匀,但细小晶粒较少。

The selective hydrogen decrepitation of NdFeB alloys was studied. It is found that in the course of hydrogen absorption of NdFeB alloys, if the amount of hydrogen absorbed by Nd-rich phases is theoretically calculated in advance and the quantities of NdFeB alloys placed in the container are quantitatively controlled, good selective hydrogen decrepitation can be completely realized under the conditions of low environmental temperature and hydrogen pressure. It is shown by SEM that the modes of fracture of selective hydrogen decrepitation are all intergranular fractures, and all of the main phase grains in decrepitated powders are monocrystalline particles, there are no cracks in the grains of Nd_2Fe_(14)B main phases. Compared with the grains of complete hydrogen decrepitation, the grains of selective hydrogen decrepitation are relatively larger and more uniform, but small grains are fewer.