微合金化2000 MPa级热成形钢的应用性能  

Application Performance of Microalloyed 2000 MPa Grade Thermoformed Steels

作　　者：曹广祥 赵隆卿 井琦 夏广明 巨萌 刘丰宁 Cao Guangxiang;Zhao Longqing;Jing Qi;Xia Guangming;Ju Meng;Liu Fengning(Global R&D Center,China FAW Corporation Limited,Changchun 130013;National Key Laboratory of Advanced Vehicle Integration and Control,Changchun 130013)

机构地区：[1]中国第一汽车股份有限公司研发总院,长春130013 [2]高端汽车集成与控制全国重点实验室,长春130013

出　　处：《汽车工艺与材料》2025年第4期46-52,共7页Automobile Technology & Material

摘　　要：研究了基于钒铌复合微合金化的铝硅镀层热成形钢在典型热成形工艺下的拉伸性能、弯曲性能、氢脆敏感性、点焊工艺及性能和涂装耐腐蚀性能。结果表明:在加热温度930℃、加热时间300 s、保压时间10 s的工艺条件下,试验材料的抗拉强度达到2 000 MPa,极限尖冷弯角大于50°,强度和韧性匹配良好;其力学性能具有明显的各向异性,在170℃保温20 min的条件下烘烤后材料的韧性明显提升;在0.1~500 s~(-1)不同应变速率下的强度和塑性指标表现出不同的应变速率敏感性特征;在100%屈服强度的弯曲应力下和空气环境中对热成形后的材料进行四点弯曲试验,静置300 h未出现裂纹和断裂,具有良好的抗氢脆性能;试验材料的点焊接头性能和涂装耐腐蚀性能满足应用要求。This study investigates the tensile properties,bending properties,hydrogen embrittlement sensitivity,spot welding performance,and coating corrosion resistance of Al-Si coated thermoformed steel based on vanadium and niobium composite microalloy under typical hot forming processes.The results indicate that under heating temperature of 930℃,heating time of 300 s and holding time of 10 s,the experimental material achieves a tensile strength of 2000 MPa and extreme tip cold bending angle is greater than 50°,demonstrating a favorable combination of strength and toughness.The mechanical properties exhibit significant anisotropy,with a notable improvement in toughness after baking at 170℃for 20 minutes.The strength and ductility parameters display varying strain rate sensitivities across different strain rates ranging from 0.1~500 s-1.In a four-point bending test at 100%yield strength in an air environment,the hot-formed material show no cracks or fractures after 300 h,indicating excellent resistance to hydrogen embrittlement.Additionally,the spot welding performance and coating corrosion resistance of the experimental material meet application requirements.

关 键 词：微合金化 热成形钢 弯曲性能 氢致延迟开裂 点焊接头性能 

分 类 号：U465[一般工业技术—材料科学与工程]