【摘要】 用热变形后的直接时效(DA处理)和标准热处理对比试验的方法,对DA处理在GH169合金中的实际应用进行了探讨。结果表明,DA处理确可提高合金的拉伸强度,并大幅度提高光滑持久寿命。但由于塑性指标的降低而导致缺口持久和周期持久寿命的降低,并使疲劳、蠕变交互作用的蠕变损伤加剧。其原因是可能DA处理过程中晶界δ相析出过少,晶界晶内强度配合不良,达不到强韧化的作用。同时指出晶粒细化,并在变形工艺中对位错组态进行控制,使δ相以合理的数量和形态析出,才能获得真正应用的DA GH169合金。更多还原

【Abstract】 For the purpose on application of direct aging (DA) GH169 in production a comparison of direct ageing treatment and standard heat treatment following hot deformation is conducted. Direct ageing treatment can get higher tensile strengthes and raise smooth specimen stress rupture lives remarkably. However, both notched specimen stress rupture aud cyclic stress rupture lives decrease because of the low ductility. The creep damage during creep and fatigue interaction condition is also enhanced. The reason may be smaller amount δ precipitate distribution at grain boundaries and the grain boundary cohesive force can not perfectly match grain strength, then the strengthening and ductility improvemeat can not reach simultaneously. Grain refinement and dislocation configuration control at the hot deformation process are most important factors to control the suitable amount and distribution of δ-phase.更多还原