碳元素配分行为对高强韧Q&P钢组织性能的影响  

Effect of carbon partition on the microstructure and properties of high strength and toughness Q&P steel

作　　者：赵星宇 王山生 庞启航 李维娟[1] 张俊凯 张大征 ZHAO Xingyu;WANG Shansheng;PANG Qihang;LI Weijuan;ZHANG Junkai;ZHANG Dazheng(School of Material and Metallurgy,University of Science and Technology Liaoning,Anshan 114051,China)

机构地区：[1]辽宁科技大学材料与冶金学院,辽宁鞍山114051

出　　处：《轧钢》2023年第5期12-17,24,共7页Steel Rolling

基　　金：国家自然科学基金项目(52004122)。

摘　　要：第3代先进高强钢中,显微组织由“奥氏体+马氏体”构成的Q&P钢最具有研发潜力。为了缩短制备工艺流程,碳元素配分机制仍需深入研究。对0.2C-1.5Si-2.0Mn系试验钢进行了“两相区淬火+配分”的热处理,并利用SEM、TEM、XRD和拉伸试验机等先进设备,研究了配分时间对试验钢板显微组织演变和力学性能的影响规律,揭示了碳元素低温配分机制。试验结果表明:当配分时间为30 s时,试验钢板的最大抗拉强度为1297 MPa;当配分时间为60 s时,试验钢板的断后伸长率达到最大值(16.7%),此时其强塑积达到最大值(21.2 GPa·%)。随配分时间的延长,残余奥氏体的体积分数呈先上升后降低的趋势;在配分时间为60 s时,残余奥氏体体积分数最大(16.7%),试验钢板综合力学性能最优,这也说明残余奥氏体的体积分数是影响Q&P钢强塑性的主导因素。The third generation of advanced high strength steels,known as Q&P steels,offer the greatest potential for advancement due to their“austenite+martensite”microstructure.The carbon partitioning mechanism still needs to be thoroughly investigated in order to speed up the preparation process.The tested steel of 0.2-1.5Si-2.0Mn was subjected to“two-phase zone quchening+partitioning”heat treatment.The effects of partitioning time on the microstructure evolution and mechanical characteristics of thetested steel were examined by using SEM,TEM,XRD,and a tensile testing machine.And the low-temperature mechanism for the partitioning of carbon elements was reavealed.The test results show that the tested steel's maximum tensile strength was 1297 MPa at a 30 s partitioning time.When the partitioning time was 60 s,the tested steel's post elongation reached its highest value(16.7%),and its strong plastic product reached its maximum value(21.2 GPa·%)at this time.With the lengthening of the partitioning time,the volume fraction of residual austenite tends to increase and then decrease.At the 60 s partitioning time,it reaches its maximum(16.7%),and the tested steel achieves the best mechanical properties,indicating that the volume fraction of residual austenite is the main factor influencing its strength and plasticity.

关 键 词：Q&P钢 热处理 配分时间 残余奥氏体 力学性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]