汽车用DP590双相高强钢板电阻点焊性能研究  

Study on Resistance Spot Welding Properties of High Strength Dual Phase DP590 Steel Plate for Automobile

作　　者：张健[1] 严思杰[2] 

机构地区：[1]湖北工业职业技术学院,湖北十堰442000 [2]华中科技大学机械科学与工程学院,湖北武汉430074

出　　处：《热加工工艺》2017年第5期231-233,共3页Hot Working Technology

摘　　要：采用中频逆变点焊机对1.6mm厚的DP590钢板进行了电阻点焊试验,并对焊点的组织和硬度进行了分析,研究了焊接电流和焊接时间对熔核直径、焊点强度的影响。结果表明,点焊接头熔合区组织为板条马氏体,粗晶区为粗大的板条马氏体,细晶区为细小的马氏体和少量的铁素体;接头熔核区平均硬度约340HV10,热影响区最高硬度为400 HV10,均高于母材。在一定范围内,熔核尺寸、焊点的正拉强度和拉剪强度均随着焊接电流和焊接时间的增加而增加,当焊接电流过大时,又呈现降低的趋势。The resistance spot welding tests of DP590 steel plate with thickness of 1.6 mm were carried out by using medium frequency inverter spot welding machine. The microstructure and hardness of welded joints were analyzed, and the effects of welding current and welding time on nugget diameter and joint strength were studied. The results show that the microstructure of welded joint is lath martensite for fusion zone, and coarsened lath martensite for CGHAZ, and fine martensite and a small amount of ferrite for FGHAZ. The average hardness of nugget zone is about 340HV10, and the highest hardness of heat affected zone is 400HV10, both of which are higher than those of base metal. With the increase of welding current and welding time within a certain range, the nugget diameter, cross tensile strength and shear tensile strength increase, while the welding current is too big, it shows a decreasing trend.

关 键 词：中频逆变点焊机 DP590 高强钢板 电阻点焊 熔核尺寸 焊点强度 

分 类 号：TG453.9[金属学及工艺—焊接]