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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 features and formation of primary α2 / γ-γ-γ-γ-γ-γbased γ-TiAl based alloys were investigated by metallographic method and TEM. It was found that the primary α2 / γ lamellae in the alloy were formed by α → αss2 → α2 + γ or α → α + γ → α2 + γ transformation. The γ-sheet is precipitated by nucleation at the original α or αss2 grain boundaries and is grown by a step-by-step mechanism of volume diffusion control. The elongation of the γ sheet at 1000 ° C is about (1.0-3.33) × 10 ( -7) m / γ. It was confirmed that the primary α2 / γ interface was semi-coherent, and the estimated α2 / γ interface energy was about 0.274J / m2.