共格γ／γ′界面对位错运动的单向阀门作用

ONE-WAY VALVE EFFECT OF COHERENT γ/γ′INTERFACE ON DISLOCATION MOVEMENT

对ＩＣ－２１８合金（一种完全共咯而且点阵错配度很小的γ′－γ两相合金）冷加工及回复中位错行为的研究表明，γ′／γ灯界面对位错运动起单向阀门作用，即允许位错自由地由γ′进入γ而严格限制其相反的运动。这种作用对该合金的冷加工及退火行为产生重要影响：在冷加工中缩短位错白由滑移距离而又避免位错在γ′中的塞积；在退火中加速γ′的位错回复，导致退火旱期大幅度的硬度下降，同时抑制再结晶起动。

It is established by investigation on dislocation behavior of IC-218 al-loy(a γ′-γ two phase alloy with full coherencv and very small mismatch)in cold-work and in recovery that a coherent γ′/γ interface acts as a one-way valve,allow-ing dislocations to move freely from from γ′into γ but not vice veras. As a result,during cold-work free slip distance of dislocations shortened while dislocation piling up inγ′ is avoided;and during annedwling dislocation recovery in γ′is obviously speeded up resulting in a sharp fall of hardness in early annealing stage and recrystallization is strongly retarded.