TRIP钢的动态拉伸变形行为研究

Dynamic deformation behaviors of TRIP-aided multiphase steels

在气动式间接杆杆型冲击拉伸试验机上对二种TRIP钢的拉伸性能随应变率的变化进行了研究,对强度随应变率的变化以及断口形貌和孔洞与变形的关系进行了分析.研究结果表明:TRIP钢在所研究的应变率范围对应变率是敏感的,屈服强度和抗拉强度随应变率增加明显提高.SEM分析发现,TRIP钢断口体现为典型的延性断裂特征,而且残余奥氏体的变形诱发相变对孔洞形成位置的影响使得其具有较好的延性.

The dynamic tensile behaviors of two TRIP - aided muhiphase steels under high-rate loading conditions were studied. The material was intereritically annealed at 780℃ and isothermally held at 400℃ so as to result in much retained austenite in the microstructure. The mechanical characterization was performed with the strain rate in a range of 300 - 1700 s^- 1 by means of the tensile split -Hopkinson bar technique. The variation tendency of tensile and yield strengths with strain rate was analyzed. The fracture surface and void were studied by means of SEM. The results show that the mechanical properties of studied steels are sensitive to strain rate, the yield and tensile strengths increase with the increase of strain rate. The studied steels have excellent tensile behavior consequentially because the TRIP effect of retained austenite during deformation postpones the formation and growth of void.