Comparisson of Recrystallization Kinetics and Grain Growth in Polycrystalline Shape Memory Alloys  

作　　者：Marcelo Nava Emmanuel Pacheco Rocha Lima Pedro Cunha de Lima 

机构地区：[1]DETEC,Instituto Federal de Educação,Ciência e Tecnologia da Bahia,Barreiras 47808-006,Brasil

出　　处：《材料科学与工程（中英文A版）》2020年第2期76-80,共5页Journal of Materials Science and Engineering A

摘　　要：The non-ferrous SMAs(shape memory alloys)have,normally,two problems that hinder the use in industrial scale:the natural aging and grain growth.The first degrades the memory effect,while the second,observed during the alloy’s mechanical processing,modifies the phase transformation temperatures.Thus,the study of recrystallization kinetics is important for enabling the control of hardened state as a function of treatment time without allowing the exaggerated grain growth.The objective of this study is to determine the recrystallization kinetics in different SMAs(Cu-14Al-4Ni,Cu-12Al-0.5Be and Ni-42Ti),based on an empirical law of J-M-A(Johnson-Mehl-Avrami),as well as their activation energies for grain growth process according to the empirical Arrhenius law.Quantitative evaluations of the grain growth kinetics over a wide range of indicated DSC(differential scanning calorimetry)temperatures have been performed.The results show that the alloy less susceptible to aging in temperatures below the recrystallization peak is the Ni-42Ti,because it presented the highest activation energy,followed by the Cu-14Al-4Ni.The equations that describe the recrystallization kinetics follow the empirical law of J-M-A.The recrystallization kinetics accompanied by hardness variation was an important tool,working as an advisor for selection of treatment time as a function of temperature.

关 键 词：SMAS NITI CuAlNi CUALBE recrystallization kinetics grain growth 

分 类 号：TG1[金属学及工艺—金属学]