摘要
研究了鞍钢试生产的热轧 SX65 双相钢电弧焊接性能。结果表明,电弧焊热影响区高温回火区内硬度明显下降,接头拉伸时均在此处断裂(抗拉强度 610 MPa)。实验证明热影响区的回火区处在熔合线的 1.5mm 左右,恰是硬度降低和强度较低的区域,是母材原始组织中铁素体位错密度降低及 15％ 的马氏体回火导致软化的原因。
The arc welding properties of hot-rolled dual-phase steel SX65developed by Anshan Iron/Steel Complex,was studied.The results showed thatthe hardness of heat-affected zone will greatly decrease in arc welding and ten-sile fractures just take place in this zone as tensile strength about 610 MPa.Also, the tempering area in heat-affected zone is found about 1.5mm distantfrom the melting line, i. e. an area where both the hardness and strength aredecreasing. This is just the reasons why the dislocation density decreases in theoriginal structure of master material and the softening caused by about 15%martensite tempered.
关键词
电弧焊
热影响区
双相钢
热轧
焊缝
are welding
heat-affected zone
dual-phase steel
