【摘要】 分析了LY12铝合金时效处理及冷热循环处理后的微屈服应力-微塑性应变曲线特征,探讨了尺寸稳定化处理对微屈服行为的影响。初步分析认为微塑变是一个原有可动位错源耗竭、位错在不利取向晶粒中滑移以及位错增殖的过程;与时效处理相比,冷热循环处理后材料的微屈服行为发生显著变化,原因在于冷热循环过程中急剧的高低温变化,使材料产生微塑性变形。更多还原

【Abstract】 The effects of dimensional stabilizing treatment on micro-yield behaviors were studied by analysing the characteristics of micro-yield stress (σ) vs. plastic strain (εp) curves of LY12 aluminium alloy treated by aging or thermal-cold cycling techniques. Preliminary results show that the micro-plastic deformation is a course of consumption of original movable dislocation resources, dislocation slip in the grains of unfavorable orientation and dislocation multiplying. Compared with aging treatment, thermal-cold cycling treatment makes marked changes of micro-yield behaviors due to the sharp change of temperature in the course of thermal-cold cycling treatment and making micro-plastic deformation in the materials.更多还原