配分温度对Q&P钢中残余奥氏体及性能的影响研究

Effect of Partitioning Temperature on Retained Austenite and Mechanical Properties of Q&P Steel

对碳-锰-硅钢淬火后在不同温度下进行配分处理,采用SEM结合EBSD技术对实验钢显微组织、残余奥氏体含量及力学性能进行表征。结果表明:随配分温度的升高,实验钢的抗拉强度降低,主要因为马氏体脱碳软化所致。残余奥氏体含量与伸长率变化趋势相同,由于在拉伸变形过程中残余奥氏体发生马氏体相变即TRIP效应,从而提高塑性。因此在300℃配分处理后的性能优异,抗拉强度为1328 MPa,伸长率为13%,残余奥氏体含量达到4.78%。

The C-Mn-Si steel is quenched and partitioned at different partitioning temperature. The microstructure and mechanical properties were measured using SEM and EBSD. The results indicate that the tensile strength decreases with the increase of temperature, which is caused by martensite decarburization. During the process of tensile deformation, because the TRIP effect of retained austenite can increase the plasticity, the variation tendency of retained austenite and elongation rate is the same. As a result, the optimal combination of strength and toughness is obtained when sample pratitioned at 300 ℃. The tensile strength and elongation are 1328 MPa and 10% repectively.