延性金属材料损伤变量的实验表征方法研究

Experimental Characterization of Damage Variables of Ductile Metal

基于微观损伤的宏观表征,采用各种实验方法对延性金属塑性变形过程中的宏观损伤变量进行表征。通过预拉伸变形的方法制备了6种不同真应变条件下的拉伸试样,并基于微小材料压缩试验机(MCT-W501)对不同预变形试样的压缩试验结果,分别采用显微硬度、弹性模量、韧性指标和电阻率等指标归一化表征了金属材料的韧性损伤,并就损伤变量的变化规律及所代表的物理含义进行分析讨论。结果表明:综合应用上述各损伤表征量并构造等效损伤曲线,能真实反映与解释延性金属材料的实际损伤过程。

Based on the macro characterization of micro-damage,macro damage variables of ductile metal in deformation process were characterized by various test methods.Six samples under different true strains were prepared by pre-tension deformation.And based on the result of compression test of different pre-deformed samples with micro compression tester（MCT-W501）,ductile damage of metal was characterized by normalization indices,such as hardness,elastic modulus,toughness indicator and resistivity.The changing rules and physical meaning of the above damage variables were discussed.The research shows that the integration of the above damage variables and equivalent damage curve should be applied in order to reflect and to explain the real process of damage of ductile metal.