论文部分内容阅读
采用E630马氏体不锈钢焊条通过手工电弧焊对0Cr15Ni7Cu2Nb马氏体不锈钢与450 MPa级低合金钢进行焊接,并对异质焊接接头显微组织、接头硬度及冲击性能进行研究。研究结果表明:低合金侧熔合线两侧区域上存在Cr的浓度梯度,使熔合线左右两侧形成明显的增脱碳层,增碳层作为硬化层导致该区域韧性降低,使该区域呈现准解理断裂,而马氏体不锈钢侧熔合线无明显增脱碳层,因而仍保持良好的韧性;粗大的枝晶状马氏体以及复合型氧化物夹杂的存在均降低了焊缝区域的韧性。
The 0Cr15Ni7Cu2Nb martensitic stainless steel and 450 MPa low alloy steel were welded by hand arc welding with E630 martensitic stainless steel electrode. The microstructure and joint hardness and impact properties of heterogeneous welded joints were studied. The results show that there is a concentration gradient of Cr on both sides of the low alloy side fusion line, so that the decarburization layer is obviously formed on the left and right sides of the fusion line. The hardened layer with carbon layer reduces the toughness of the region, Cleavage fracture, while the martensite stainless steel side of the fusion line decarburization layer did not significantly increase, and thus still maintain good toughness; coarse dendritic martensite and composite oxide inclusions are present in the weld zone to reduce the toughness .