Ti-Ni-Cu形状记忆合金急冷条带的显微组织  

Microstructure of Rapidly-solidified Ti-Ni-Cu Shape Memory Alloy Ribbons

作　　者：何文军[1] 闵光辉[1] 于化顺[1] 

机构地区：[1]山东大学材料科学与工程学院

出　　处：《特种铸造及有色合金》2007年第2期153-156,共4页Special Casting & Nonferrous Alloys

基　　金：国家外专局聘请外国专家重点项目(20050360646)

摘　　要：研究了Ti51.7Ni24.5Cu23.8形状记忆合金条带急冷态和退火态下的组织变化。结果表明,急冷态组织主要为非晶态,同时含有部分晶化相B2和B19。B19马氏体变体形貌多样,呈针状、条状、粗片状及钩状。急冷条带在5℃/min的连续加热下,晶化开始温度为436℃。利用Kissinger方法确定其晶化激活能为444.7kJ/mol。条带经400℃低温退火后晶相主要为单变体B19,部分晶粒内部马氏体双变体自协作成垂直关系。马氏体在晶界处形核并向晶内生长,急冷态下的钩状马氏体变体经退火后消失。The microstructure of Ti_ 51.7 Ni_ 24.5 Cu_ 23.8 shape memory alloy ribbons prepared by rapid solidification has been observed in the conditions of spinning and annealing respectively. The results show that microstructure of as-spun ribbons is mainly composed of amorphous phase embedded with a small amount of crystalline particles that is indexed by B2 or B19. B19 martensites variants show various morphologies such as needle, coarse plate, strip and hook. The initial crystallization temperature of 436 ℃ can be observed and the crystallization activation energy of 444.7 kJ/mol of the as-spun ribbons can be determined by the Kissinger's equation at a heating rate of 5 ℃/min by DSC linear scanning. Crystallization structure of the ribbon is mainly composed of single-pair variant B19 martensites, in which there exist two pairs of variants self-accommodated with perpendicular orientation in some particle, and the absence of the hook-like martensite variants can be found and new martensite is preferred to nucleate at the grain boundary to growth towards grain, with annealing at 400 ℃.

关 键 词：快速凝固 Ti—Ni—Cu合金 条带 显微组织 

分 类 号：TG139.6[一般工业技术—材料科学与工程]