Present work aims to assess tensile and high cycle fatigue (HCF) performance of dual-phase (DP590) steel subjected to uniaxial and equi-biaxial pre-strain. Pre-strain increases material’s strength, reduces ductility and simultaneously enhances HCF performance, quantified by increased material’s tensile yield strength 12% & 21%, ultimate tensile strength 6% & 7%, endurance limit 11% & 18%, after 10% uniaxial and equi-biaxial pre-strain. The rotation of one maximum shear stress plane during uniaxial re-loading after equi-biaxial pre-strain results in increased fatigue life. Finite element analysis suggests an alteration in the location of deformation concentration zone during uniaxial fatigue cycling of equi-biaxial pre-strain material.

目前的工作旨在评估双相 (DP590) 钢在单轴和等双轴预应变下的拉伸和高周疲劳 (HCF) 性能。预应变增加材料的强度，降低延展性，同时提高 HCF 性能，量化为材料的拉伸屈服强度增加 12% 和 21%，极限拉伸强度 6% 和 7%，耐力极限 11% 和 18%，单轴和 10% 后等双轴预应变。在等双轴预应变后单轴重新加载期间，一个最大剪应力平面的旋转导致疲劳寿命增加。有限元分析表明，在等双轴预应变材料的单轴疲劳循环过程中，变形集中区的位置发生了变化。