冷轧压下量对TWIP钢组织与性能的影响

Effect of cold reduction on microstructure and properties of TWIP steel

采用静态拉伸、金相、SEM、TEM等方法对冷轧压下量为50%、60%和70%的TWIP钢板热处理后的组织与性能进行了研究。结果表明,TWIP钢变形前后的组织均为单相奥氏体,其中冷轧压下量为50%的TWIP钢板力学性能最优,该TWIP钢退火后的晶粒能够为孪晶的生成和长大提供更有效空间。冷轧压下量对TWIP钢的耐腐蚀性影响很小,TWIP钢的腐蚀电位在-0.69 V左右,腐蚀方式为较为典型的点状腐蚀。TWIP钢断口呈等轴状韧窝结构,冷轧压下量为50%的试验钢的断口呈现出更好的塑性特征;冷轧压下量为50%的TWIP钢微观组织中观察到了条束状多系孪晶。

Microstructure and properties of the annealed TWIP steel,with cold rolling reductions of 50%,60% and 70%,were investigated by static tensile test,metallography,SEM and TEM.The results show that the microstructure of the TWIP steel before and after deformation is austenitic single phase.The TWIP steel possesses the best mechanical properties when the cold rolling reduction is 50%,and the grains of this steel have effective space for the creation and growth of twins;the cold rolling reduction has little effect on the corrosion resistance of the TWIP steel,the corrosion potential of them is about-0.69 V and the corrosion mechanism is pitting corrosion;the fracture of the TWIP steel shows equiaxed dimples,the fracture exhibit better plastic characteristic when the cold rolling reduction is 50%,moreover,when the cold rolling reduction is 50%,more deformation twin systems can be observed in the TWIP steel.