热输入对高强度气体保护焊丝焊缝金属强韧性的影响

Effect of Heat Input on Strength and Toughness of Welding Metal of High Strength Wire

摘要: 采用拉伸、冲击试验和显微组织观察,研究了热输入在10~27 kJ/cm时对超低碳气体保护焊丝焊缝金属强度、韧性及显微组织的影响。结果表明,随着焊接热输入的增加,焊缝金属的强度和韧性呈下降趋势,其原因在于,随热输入的提高,合金元素烧损增多,焊缝冷却时间延长,焊缝金属高温再热区中强度较低、韧性较差的铁素体含量增加。

Abstract: With tensile and impact tests and microstructure observation,the effect of heat input(from 10 kJ/cm to 27 kJ/cm) on the strength and toughness of welding metal made by high strength welding wire was investigated.The results show that the strength and toughness decrease as the heat input increase.The reason lays to more loss of alloy elements,elongated cooling time of welding metal,more ferrite of low strength and tougness in high temperature reheating region as the heat input increase.