Devitrification process in rapidly solidified A1-Ni-Cu-Nd metallic glass

来源期刊：中南大学学报(英文版)2003年第3期

论文作者：肖于德 黎文献 N. Clavaguera D. Jacovkis M. T. Clavaguera-Mora J. Rodriguez-Viejo

文章页码：163 - 167

Key words：rapid solidification; Al-rich amorphous alloy; devitrification process; phase transformation

Abstract: In the present study, rapidly solidified ribbons of A18, Ni, Cu3 Nd3 metallic glass was prepared by using melt spinning. Devitrification process of the totally amorphous ribbons was investigated by high temperature X-ray diffraction analysis, combining with differential scanning calorimetry, under continuous and isothermal heating regime. The X-ray diffraction intensity and full width at the half maximum (FWHM) were analyzed to investigate the increase of crystallized amount and growth of a-A1 crystal particles. The results show that under continuous heating regime, the metallic glass denitrifies via two main stages: primary crystallization, resulting in two-phase mixture of a-A1 plus residual amorphous phase, and secondary crystallization, corresponding to rapid precipitation of some inter-metallic phases in the form of dispersion or eutectic mixture. Under isothermal heating regime, only A1 crystal precipitates from the Al-rich amorphous matrix at low temperature, and when heating at 280 0C only Al crystal precipitates within a short time, and then AleCu, Nd forms, followed by A1₃ Ni, in the residual amorphous phase. When heating at higher temperature or for longer time, AI？Nd₃ forms, the amorphous phase disappears, and the ribbons develop into polycrystalline morphologies with multiply phase mixture of a-Al, Al$ Cuo- Nd, Al₃ Ni, and Al？ Nd₃.