QP980和DP980高强钢板的抗延迟断裂性能  

Delayed fracture resistance performance for high strength steel sheet QP980 and DP980

作　　者：濮振谦 林建平[1,2] 叶又[3] 赵强[1,2] Pu Zhenqian Lin Jianpmg Ye You Zhao Qiang(Shanghai Key Laboratory of Vehicle Aerodynamics and Vehicle Thermal Management Systems, Tongji University, Shanghai 201804, China School of Mechanical and Energy Engineering College, Tongji University, Shanghai 201804, China Pan Asia Technical Automotive Center, Shanghai 201201, China)

机构地区：[1]同济大学上海市地面交通工具空气动力与热环境模拟重点实验室,上海201804 [2]同济大学机械与能源工程学院,上海201804 [3]泛亚汽车技术中心有限公司,上海201201

出　　处：《锻压技术》2017年第4期153-158,共6页Forging & Stamping Technology

基　　金：国家自然科学基金资助项目(51375346)

摘　　要：高强钢零件的延迟断裂现象是汽车使用安全性的严重威胁。针对QP980和DP980两种高强度汽车用钢板,基于单向拉伸实验和电化学充氢,分析了预变形对高强钢充氢后的伸长率及强度的损失规律,对比了DP980和QP980的抗延迟断裂性能。研究发现,预应变从0至7%变化时,QP980和DP980均发生严重的塑性损失,但在同一预应变下,QP980的各项塑性损失几乎均大于DP980,得出QP980的抗延迟断裂性能较DP980差。通过断口形貌分析,发现QP980相比DP980更易受到氢的侵入从而脆化,从而验证了实验结果的准确性和科学性。Delayed fracture phenomenon of high strength steel parts is a serious threat to the safety of automobile use. For high strength steel sheet DP980 and QP980 used in the vehicle,based on the uniaxial tension test and electrochemical hydrogen charging,the loss regularities of pre-deformation on elongation after high strength steel sheet hydrogen charging and strength change were studied,and the delayed fracture resistance performances for high strength steel sheet DP980 and QP980 were compared. The result shows that when the prestrain changes from 0 to 7%,both materials of DP980 and QP980 have great ductility losses,but with the same pre-strain,the ductility loss of QP980 is always greater than that of DP980. So,it is concluded that the delayed fracture resistance performance of QP980 is weaker than that of DP980. By the analysis of fracture surface morphology,it is found that QP980 is more permeable by hydrogen than DP980,and the experiment results are of accuracy and scientificity.

关 键 词：预应变 高强钢 延迟断裂 DP980 QP980 

分 类 号：TG142.12[一般工业技术—材料科学与工程]