熔融6061和4043铝合金在纯钛表面的反应润湿

利用改良座滴法研究了高真空条件下熔融6061和4043铝合金在600,650,700℃分别与纯钛(TA2)的反应润湿行为。结果表明:Al/Ti体系属于典型的反应润湿,铝合金中微量的Si元素在界面上产生了明显富集且满足热力学条件;界面上形成了富Si的致密的层片状Ti_7Al_5Si_(12)相,致密层产生后阻碍熔体润湿母材;Ti_7Al_5Si_(12)相的分解及三相线附近疏松的粒状Al_3Ti相产生后能够破除钛表面的氧化膜,进而促进润湿;6061/TA2和4043/TA2两润湿体系铺展动力学均可由反应产物控制(Reaction Product Model)模型描述,整个润湿铺展过程分为两个阶段,即先呈指数铺展、后呈线性铺展;6061铝合金对应两个阶段的铺展活化能分别为56kJ/mol和112kJ/mol,4043铝合金以指数铺展为主,铺展活化能为47kJ/mol,Ti_7Al_5Si_(12)相的分解对应于指数铺展阶段。

Reactive Wetting of Pure Titanium by Molten 6061 and 4043 Aluminum Alloys

The wetting of TA2 pure Ti by two industrial grade Al alloys (i .e .,6061 Al and 4043 Al al-loys) was studied by using the modified sessile drop method at 600 ,650 ,700℃ under high vacuum . The results show Al/Ti system is a typical reactive wetting ,the small amount of alloying element Si in the Al alloys can cause significant enrichment at liquid/solid interface and satisfy thermodynamic condition;the formation of the Si-rich phase (Ti7 Al5 Si12 ) strangling material exchange at triple line zone;Ti7 Al5 Si12 decomposition and Al3 Ti formation can remove the oxide film and promote wetting ;the spreading dynamics can be described by reaction product control model ,further the whole wetting behavior can be divided into two stages :the first stage for the nonlinear spreading and the second stage forthe linear spreading ;the activation energies w hich are 56kJ/mol ,47kJ/mol for nonlinear stages of 6061 Al and 4043 Al alloys ,and 112kJ/mol for linear stage of 6061 Al alloys ,respectively ,Ti7 Al5 Si12 decomposition is corresponding to the nonlinear spreading .