【摘要】 以薄壁管试样为研究对象,在高温下进行拉扭组合的比例与非比例循环加载,对GH4169镍基合金材料的循环硬化软化特性、塑性应变特征以及蠕变行为进行分析。研究结果表明,高温下GH4169材料的循环硬化软化与等效应变幅值、温度、应变加载路径和加载频率相关,在无保持时间的高温疲劳试验中仍然存在蠕变现象。微观结构分析显示在等效应变为0.8%的试件断口中有混合断裂特征,说明材料承受着疲劳和蠕变共同作用。更多还原

【Abstract】 The cyclic hardening and softening properties, as well as the plastic strain and creep behaviors of GH4169 Nickel-based alloy were investigated under proportional and nonproportional tension-torsion cyclic loading and high temperature condition with tubular specimens. The results show that the cyclic hardening and softening properties depend on the equivalent strain range, temperature, strain loading paths and frequencies. The creep behavior exists in the fatigue process at high temperature without hold-time. The mixed fracture phenomena was observed by micro-structure analysis in the case of the equivalent strain of 0.8%, which show further that the material stands the fatigue-creep action.更多还原