微米级Nd-Ni合金颗粒的元素深度分布

NdNi_5是一种贮氢材料,通常采用高频熔炼法来制取.本文采用还原扩散法,用氢化钙(和它分解出的钙)把Nd_2O_3还原成Nd,接着Nd和Ni进行反应扩散,最后得到NdNi_5.将一定配比的Ni粉、Nd_2O_3、CaH_2混匀后在氢气中加热到1000℃,恒温4h,洗涤后得到灰色粉末

Element depth distribution of .mu.m grade Nd-Ni alloy grain

The reductive diffusion process was studied on the basis of the depth profiling. The phase and element depth profiling of mm grade Nd-Ni alloy were determine in the preparation of H absorption material by the reductive-diffusion process. Relative content of Ni, Nd, and Ca at different depths were studied using chem. anal., x-ray diffraction anal., x-ray photoelectronic spectroscopy, and SEM. The surface phase in Nd-Ni alloy was nearly pure Nd when the temperature was just 1000? At the depth >100 ? the presence of Ni and Ca were observed Nd and Ni diffuse into each other, but rate of diffusion of Nd is faster than that of Ni. When the temperature is 1000? the relative content of Ni and Ca increases but Nd decreases with increasing depth. When the reduction- is carred out at constant temperature, the Ca content in the products decreased with increasing time, and at 1000?for 4 h, the phase of the product is NdNi5 with Ca content of 0.3%.