|关键词: 焊条 熔敷金属 显微组织
|Microstructure and properties of new R407C electrode deposited metal
Wang Qingjiang1,2, Wang Meng1,2, Liu Mangyu1,2, Sun Tingting1,2, Zhang Linli3
|The 12Cr2Mo1R steel electrode relies on imports for long time. While, the main problem for domestic steel hydrogenation unit is that it can’t meet the low temperature impact toughness at -30 ℃ and long-term anti-temper brittleness requirements. The microstructure of the deposited metal of the newly developed R407C electrode was observed by metallographic microscope, and the properties were tested by tensile and impact tests. The results showed that the deposited metal structure of R407C electrode was tempered bainite structure at PWHT. With an increase in tempering parameters, the grain gradually grew up, the bulk ferrite content increased, the structure gradually transformed into ferrite + carbide, and its strength and toughness gradually decreased. As the heat input of welding increased, the massive ferrite grains in the weld increased. And its toughness was gradually reduced.
|Key words: electrode deposited metal microstructure