冷速对液态Ti_3Al合金快速凝固过程中微观结构变化的影响  

The Effect of Cooling Rate on the Microstructure Change During Rapid Solidification of Liquid Ti_3Al Alloy

作　　者：秦云翔[1] 谢泉[2] 高廷红[2] 闫万珺[2] 郭笑天[2] 范梦慧[2] 

机构地区：[1]贵州大学材料与冶金工程学院,贵州贵阳550025 [2]贵州大学理学院,贵州贵阳550025

出　　处：《现代机械》2013年第1期80-82,85,共4页Modern Machinery

基　　金：国家自然科学基金项目(61264004);贵州省科技攻关项目(黔科合GY字[2011]3015);贵州省科技创新人才团队建设专项资金项目(黔科合人才团队[2011]4002);贵州省国际科技合作项目(黔科合外G字[2012]7004)

摘　　要：采用分子动力学方法模拟研究了不同冷速条件下液态Ti3Al合金的凝固过程。采用对相关函数法、原子团类型指数法(CTIM)对凝固过程中团簇结构的变化进行了分析。结果表明:在以1×1012K/s,1×1013K/s,1×1014K/s三种不同冷速条件下,系统都形成了以(12 0 12 0)基本原子团为主的非晶态结构,冷速对于Ti3Al合金凝固过程微观结构的影响主要是通过(12 0 12 0)基本原子团数目变化体现出来,(12 0 12 0)基本原子团在Ti3Al合金快速凝固过程团簇结构演变中起了主要作用。冷速越低,Ti3Al合金的玻璃态转化温度越低,体统形成的(12 0 12 0)基本原子团数目越多,非晶体的结构越稳定。A simulation study has been performed for the solidification of liquid Ti3A1 alloy at different cooling rate by molecular dynamics method. The pair distribution function g（r） curves and the cluster-type index method were used to analyze the changes of clusters structures during rapid solidification processes. It is showed that amorphous structures are formed mainly with the basic cluster （12 0 12 0） at the cooling rate of 1 x 10nK/s,1 x 10~3K/s and l x 10~4K/s in the system. The effect of cooling rate on the structure during solidification process of liquid Ti3 A1 alloy is mainly reflected by changes in the number of the （ 12 0 12 0） basic cluster. The basic cluster （ 12 0 12 0） plays a key role in evolution of cluster structures during rapid solidification processes. With lower cooling rate, there are more number of the （ 12 0 12 0）basic clusters formed, the amorphous structure is more stable.

关 键 词：液态Ti3Al合金 凝固过程 原子团类型指数法 团簇结构 

分 类 号：O469[理学—凝聚态物理]