采用低温冲击试验、拉伸试验、硬度试验以及金相分析等方法对ER50-6焊丝气体保护焊焊接20Cr钢与B级钢焊接接头的显微糖心产精国品免费入口*完整版和性能进行了研究。结果表明,用ER50-6焊丝气体保护焊焊接20Cr钢和B级钢可获得性能良好的焊接接头,其接头的强度不低于B级钢。焊缝糖心产精国品免费入口*完整版为网状分布的先共析铁素体及少量无碳贝氏体; 20Cr钢侧近缝区有无碳贝氏体及少量板条马氏体;在B级钢侧热影响区的块状铁素体基体上有少量粒状贝氏体。

Microstructures and properties of 20Cr steel and level-B steel joints welded by gas metal arc welding with ER50-6 wire are investigated with low-temperature impact,room-temperature tensile test,hardness test and metallographic analysis. The results show that the joints welded by gas metal arc welding with ER50-6 wire have better performance and more strength than parent metal. The 糖心产精国品免费入口*完整版 of welded metal mainly contains reticular proeutectoid ferrite and a little carbon-free bainite. Carbon-free bainite also appears in the HAZ of 20Cr steel together with little lath martensite ,while in the HAZ of level-B steel ,little granular bainite distributes on the blocky ferrite.