ECAP变形对20MnSi钢组织与性能的影响

Effects of ECAP on Microstructures and Mechanical Properties of 20MnSi Steel

采用C方式等径弯曲通道变形(Equal Channel Angular Pressing,简称ECAP)对20MnSi钢进行了4道次室温变形,研究了变形道次对显微组织和力学性能的影响。结果表明,铁素体组织随变形道次的增加逐渐演变为等轴状大角度晶界的亚微晶组织;试验用钢的硬度和强度随变形道次的增加而增加,4道次后强度有所降低;在本试验条件下,珠光体组织中的片状渗碳体表现出很强的塑性变形能力。

20MnSi Steel was successfully processed by equal channnel angular pressing（ECAP） of four passes with route C at room temperature,and the influences of ECAP pass on microstructures and mechanical properties were examined.The results indicate that the initial ferrite microstructure gradually developed into the equiaxed submicrometer grain microstructure with high angle boundaries with increasing the pass number.The bardness and strength of the steel increased with the increasing pass number,but the strength reduced after the fourth pass.Under the present ECAP conditions,the cementite in the lamellar pearlite exhibited the considerable plastic deformation capability.