Formation mechanism and growth kinetics of TiAl_(3) phase in cold-rolled Ti/Al laminated composites during annealing  

冷轧Ti/Al层状复合材料中TiAl3相在退火过程中的形成机理及生长动力学

作　　者：Jian-yu ZHANG Yan-hui WANG Zheng LÜ Qing-an CHEN Ya-yu CHEN He-zong LI 张建宇;王艳辉;吕征;陈庆安;陈亚宇;李河宗(河北工程大学机械与装备工程学院,邯郸056038;河北工程大学河北省智能工业装备技术重点实验室,邯郸056038)

机构地区：[1]School of Mechanical and Equipment Engineering,Hebei University of Engineering,Handan 056038,China [2]Key Laboratory of Intelligent Industrial Equipment Technology of Hebei Province,Hebei University of Engineering,Handan 056038,China

出　　处：《Transactions of Nonferrous Metals Society of China》2022年第2期524-539,共16页中国有色金属学报（英文版）

基　　金：the financial supports from the S&T Program of Hebei Province,China(No.20373901D);the National Natural Science Foundation of China(Nos.51807047,51804095);the National Science Foundation of Hebei Province,China(No.E2019402433);the Youth Top Talents Science and Technology Research Project of Hebei Province University,China(No.BJ2019003);the Research and Development Project of Science and Technology of Handan City,China(No.19422111008-19).

摘　　要：Cold-rolled Ti/Al laminated composites were annealed at 525−625℃for 0−128 h,and the interfacial microstructure evolution was investigated.The results indicate that only the TiAl_(3) phase was formed at the Ti/Al interface;most of TiAl_(3) grains were fine equiaxed with average sizes ranging from hundreds of nanometers to several microns and the TiAl_(3) grain size increased with increasing annealing time and/or temperature,but the effect of annealing temperature on the TiAl_(3) grain size was far greater than that of annealing time.The growth of the TiAl_(3) phase consisted of two stages.The initial stage was governed by chemical reaction with a reaction activation energy of 195.75 kJ/mol,and the reaction rate constant of the TiAl_(3) phase was larger as the Ti/Al interface was bonded with fresh surfaces.At the second stage,the growth was governed by diffusion,the diffusion activation energy was 33.69 kJ/mol,and the diffusion growth rate constant of the TiAl_(3) phase was mainly determined by the grain boundary diffusion owing to the smaller TiAl_(3) grain size.将冷轧Ti/Al层状复合材料在525~625℃温度范围内退火0~128 h,并对复合材料的界面显微组织演变进行研究。结果表明,仅金属间化合物TiAl_(3)相在Ti/Al界面形成,大多数TiAl_(3)晶粒为细小的等轴晶,其平均尺寸从数百纳米到数微米,且随温度和/或退火时间的增加而增加,其中退火温度对晶粒尺寸的影响远大于退火时间的影响。TiAl_(3)相的生长可分为两个阶段:在初始阶段,TiAl_(3)相的生长由化学反应控制,反应激活能为195.75 kJ/mol,另外,由于冷轧方法制备的Ti/Al层状复合材料的界面与新鲜表面结合,TiAl_(3)相的反应速率常数较大;在第二阶段,TiAl_(3)相的生长由扩散控制,扩散激活能为33.69 kJ/mol,另外,由于TiAl_(3)相晶粒尺寸细小,TiAl_(3)相的扩散生长速率常数由晶界扩散决定。

关 键 词：Ti/Al laminated composites ANNEALING growth kinetics TiAl3 phase formation mechanism 

分 类 号：TB331[一般工业技术—材料科学与工程]