基于Johnson-Cook的高强度双相钢断裂失效表征模型  

Fracture failure characterization model on high-strength dual-phase steel based on Johnson-Cook model

作　　者：余宏军 张驰 Yu Hongjun;Zhang Chi(School of Mechatronics and New Energy Vehicles,Yichun Vocational Technical College,Yichun 336000,China;School of Physical Science and Technology,Yichun University,Yichun 336000,China)

机构地区：[1]宜春职业技术学院机电与新能源汽车学院,江西宜春336000 [2]宜春学院物理科学与工程技术学院,江西宜春336000

出　　处：《锻压技术》2025年第4期257-266,共10页Forging & Stamping Technology

基　　金：江西省高等学校教学改革研究项目(JXJG-19-60-4);江西省教育厅科技基金资助项目(GJJ211611)。

摘　　要：对高强度双相钢DP780开展断裂失效性能和表征模型分析。首先,采用混合硬化模型和Johnson-Cook高应变速率本构模型对其静态、动态力学性能曲线进行拟合,设计了5种断裂失效试样并通过试验获取断裂时的极限塑性应变。其次,对各试样开展仿真分析,以力-位移曲线的最小误差为目标,对混合硬化模型调节系数开展优化,提取断裂区域的应力三轴度,并采用Johnson-Cook模型拟合失效曲线。最后,通过5种试样的穿孔试验对模型进行验证。结果表明:Swift和Hockett-Sherby混合硬化模型的调节系数最优值为0.685;不同试样的力-位移曲线的仿真与试验结果重合度较高,最大载荷和最大失效位移的误差不超过5%,破裂区域位置基本一致。研究证明所搭建的模型对材料力学特性和断裂性能表征较好,可应用于整车碰撞仿真。The fracture failure performance and characterization model of high-strength dual-phase steel DP780 were analyzed.Firstly,the static and dynamic mechanical properties curves were fitted by the hybrid hardening model and Johnson-Cook high strain rate constitutive model,and five fracture failure specimens were designed and the ultimate plastic strain at fracture was obtained by experiments.Secondly,simulation analysis was conducted on each specimen,taking the minimizing error of load-displacement curve as the goal,the coefficients of the hybrid hardening model were optimized to extract the stress triaxiality of fracture area,and the failure curve was fitted by the Johnson-Cook model.Finally,the model was verified by the perforation experiment of each specimen.The results indicate that the optimal adjustment coefficient for the Swift and Hockett-Sherby hybrid hardening model is 0.685,the load-displacement curves of different specimens have a high degree of coincidence with the experiment results,and the errors of maximum load and maximum failure displacement do not exceed 5%,and the locations of fracture area are basically consistent.Thus,the research proves that the constructed model has a good characterization of mechanical properties and fracture performance for the material and is applied to the whole vehicle collision simulation.

关 键 词：高强度双相钢 断裂失效 本构模型 混合硬化模型 穿孔试验 

分 类 号：TG142.1[一般工业技术—材料科学与工程]