高密度脉冲电流对冷轧钛板力学性能的改善(英文)

Improvement of mechanical properties of cold-rolled commercially pure Ti sheet by high density electropulsing

对冷轧钛板试样进行高密度脉冲电流处理(最大电流密度7.22kA/mm2,周期110μs)。应用单向拉伸试验对不同状态试样的力学性能进行测试,通过光学金相显微镜(OM)观察试样的微观组织形貌。结果表明,脉冲电流处理后,在钛板材试样中形成细小的等轴再结晶晶粒和片层组织共存的组合组织。由于晶粒的细化和片层组织的出现,使得脉冲电流处理试样的强度明显高于普通退火试样的,最大相差100MPa。在屈服强度和抗拉强度大幅度提高的同时,脉冲电流处理试样仍然保持良好的塑性,具有更好的强度和韧性。脉冲电流是改善冷轧钛板力学性能的一种有效方法。

Specimens cut from the cold-rolled commercially pure （CP） Ti sheet were treated by high density electropulsing （the maximum current density 7.22 kA/mm2, pulse period 110 las）. The deformation behaviors of the CP Ti specimens at different states were determined by the uniaxial tensile test. The microstructure morphologies were observed by the optical microscopy. The results show that the electropulsing induced formation of f＇me equal-axial grains and lamellar microstructures, which leads to the strength of the electropulsed CP Ti higher than that of the conventional annealed CP Ti. After electropulsing, the tensile strength and yield strength are increased by 100 MPa. And the electropulsed CP Ti has a good plasticity. The experimental results demonstrate that the electropulsing provides an effective approach to enhance the strength of cold-rolled CP Ti sheet and retain the required high ductility.