摘要
利用金相法及TEM研究了γ-TiAl基（γ十α2）双相合金初生（α2／γ）片层形成过程中的界面特征及形成方式．发现合金中初生α2／γ片层组织是通过α→αss2→α2＋γ或α→α＋γ→α2＋γ相变方式形成的．γ片层的析出是通过在原α或αss2晶界处形核，以体积扩散控制的台阶机制生长，1000℃时γ片层的伸长速度约为（1．0—3．33）×10(-7)m／γ．并确定初生α2／γ界面为半共格，估算α2／γ界面能约为0．274J／m2．
The interfacial character and formation of primary α2/γ lamellae in the or orsupersaturated α2 matrix for γ-TiAl-based (α2+γ) two-phase alloy were investigated by opticalmicroscopy and TEM. The formation of primary α2/γ lamellae is through either α-α2γorα- α+γ -α2+γ transformation. Theγ lamella nucleates at grain boundary and growsthrough the ledge mechanism controlled by volume diffusion process. The growth velocity of 7lamellae along the longitudinal direction in the matriX is about (1.0 - 3.33) x 10(-7) m/s. Theprimary or2/7 interface was determined to be sendcoherent, and the α2/γ interfacial energy wasestimated to be about 0.274 J/m2.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1998年第12期1279-1283,共5页
Acta Metallurgica Sinica
基金
国家自然科学基金!59371025
