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

作　　者：肖于德 黎文献 D.Jacovkis N.Clavaguera M.T.Clavaguera-Mora J.Rodriguez-Viejo 

机构地区：[1]College of Materials Science and Engineering,Central South University, Changsha 410083, China Grup de Fisica de Materials I, Departament de Fisica,Universitat Autonoma de Barcelona, 08193 Bellaterra, Spain [2]Fisica de l'Estat Solid, Facultat de Fisica, Universitat de Barcelona,Diagonal 647, 08028 Barcelona, Spain [3]College of Materials Science and Engineering, Central South University, Changsha 410083, China [4]Grup de Fisica de Materials I, Departament de Fisica, Universitat Autonoma de Barcelona, 08193 Bellaterra, Spain [5]Fisica de l'Estat Solid, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona, Spain)

出　　处：《Journal of Central South University of Technology》2003年第3期163-167,共5页中南工业大学学报（英文版）

基　　金：Project (1999SGR-00336) supported by the Comission Interdepartmental de Ciencia i Tecnologia of Spain; ;Project supported by Agencia Espanola de Cooperanion International and China Scholarship Council

摘　　要：In the present study, rapidly solidified ribbons of Al87 Ni7Cu3 Nd3 metallic glass was prepared by usingmelt spinning. Devitrification process of the totally amorphous ribbons was investigated by high temperature X-raydiffraction analysis, combining with differential scanning calorimetry, under continuous and isothermal heating re-gime. The X-ray diffraction intensity and full width at the half maximum (FWHM) were analyzed to investigate theincrease of crystallized amount and growth of α-Al crystal particles. The results show that under continuous heatingregime, the metallic glass devitrifies via two main stages: primary crystallization, resulting in two-phase mixture ofα-Al plus residual amorphous phase, and secondary crystallization, corresponding to rapid precipitation of some in-ter-metallic phases in the form of dispersion or eutectic mixture. Under isothermal heating regime, only Al crystalprecipitates from the Al-rich amorphous matrix at low temperature, and when heating at 280 ℃ only Al crystal pre-cipitates within a short time, and then Al8 Cu4 Nd forms, followed by Al3 Ni, in the residual amorphous phase. Whenheating at higher temperature or for longer time, Aln Nd3 forms, the amorphous phase disappears, and the ribbonsdevelop into polycrystalline morphologies with multiply phase mixture of a-Al, Al8 Cu4 Nd, Al3 Ni, and Al11 Nd3.In the present study, rapidly solidified ribbons of Al_(87) Ni_7Cu_3Nd_3metallic glass was prepared by using melt spinning. Devitrification process of the totally amorphousribbons was investigated by high temperature X-ray diffraction analysis, combining withdifferential scanning calorimetry, under continuous and isothermal heating regime. The X-raydiffraction intensity and full width at the half maximum (FWHM) were analyzed to investigate theincrease of crystallized amount and growth of α-Al crystal particles. The results show that undercontinuous heating regime, the metallic glass devitrifies via two main stages: primarycrystallization, resulting in two-phase mixture of α-Al plus residual amorphous phase, andsecondary crystallization, corresponding to rapid precipitation of some inter-metallic phases in theform of dispersion or eutectic mixture. Under isothermal heating regime, only Al crystalprecipitates from the Al-rich amorphous matrix at low temperature, and when heating at 280℃ only Alcrystal precipitates within a short time, and then Al_8Cu_4Nd forms, followed by Al_3Ni, in theresidual amorphous phase. When heating at higher temperature or for longer time, Al_(11)Nd_3 forms,the amorphous phase disappears, and the ribbons develop into polycrystalline morphologies withmultiply phase mixture of α-Al, Al_8Cu_4Nd, Al_3Ni, and Al_(11)Nd_3.

关 键 词：rapid SOLIDIFICATION Al-rich AMORPHOUS alloy DEVITRIFICATION process phase TRANSFORMATION 

分 类 号：TG111.4[金属学及工艺—物理冶金]