焊后回火温度对G115钢熔敷金属组织及室温力学性能的影响

Effect of post-weld tempering temperature on microstructure and room temperature mechanical properties of G115 steel deposited metal

采用G115钢焊条焊接了熔敷金属试板,然后分别在760、780、800、820℃下进行了焊后回火热处理,并对不同回火温度下试样的力学性能和显微组织进行了分析。结果表明,G115钢熔敷金属的最佳回火温度为800℃,随着回火温度的升高,析出相M_(23)C_(6)有长大的趋势。760~820℃回火后的冲击断口表现为韧窝断裂和准解理断裂特征,在韧窝内存在焊接冶金脱氧过程中形成的球形第二相粒子。

G115 steel filler rod was welded on a steel test plate,and then the post-weld tempering for the plate was carried out at 760,780,800 and 820℃,respectively.The mechanical properties and microstructure of the weld-deposited steel plate under different tempering temperatures were analyzed.The results show that the best tempering temperature of the G115 steel deposited on the plate is 800℃.With the increases of the tempering temperature,the precipitation phase M_(23)C_(6) has a growing-up trend.The impact fracture of the steel plate tempered at 760-820℃is characterized by dimple fracture and quasi-cleavage fracture.Spherical second phase particles are observed in the dimples which formed during the deoxidation reaction in welding metallurgy process.