【摘要】 在对称恒应力和对称恒塑性应变两种不同循环方式下,冷变形 Cu 应力应变行为在拉压两个方向上的不对称性分别表现为循环蠕变和平均应力。本文用长程内应力理论分析了这种不对称性的特点,比较了循环蠕变和平均应力在循环中的变化,发现两者的基本规律完全一致,但应力控制对不对称性有"放大"效应,这来自循环对蠕变的累积。文章还分析了载荷幅和预变形度对循环第一周蠕变和平均应力的影响。更多还原

【Abstract】 The asymmetry in tension and compression of the cold prestrained Cu was displayed as cyclic creep or mean stress in fatigue tests under symmetrical constant stress control or symmetrical constant plastic strain control respectively.This asymmetry was analyzed with the long-range internal stress theory.The ch- anges in cyclic creep and mean stress during cycling were compared,and their behavior was found fairly co- incident.But the stress control mode has the "magnifying" effect on the asymmetry the effect is caused by creep cummulation during cycling.The effects of load amplitude and prestrain degree on the creep and mean stress in the first cycle were analyzed also in the present paper.更多还原