摘要
Abstract
To promote innovation in welding materials and improvement in welding processes for 9%Cr steel,the research progress on toughness of deposited metal of welding consumables for 9%Cr steel was summaried and analyzed.The results show that the principle of"quasi-composition matching"can be adopted in the selection of welding consumables of 9%Cr heat-resistant steel,and the martensite structure in weld metal is inevitable.The toughness value lower than the base metal appears in the impact toughness sample of deposited metal for 9%Cr steel welding consumables at 20℃.Among the factors influencing the toughness of deposited metal,the influence of welding method is mainly controlled by the oxygen content in deposited metal;in the influence of chemical composition of deposited metal,many elements which are beneficial to creep strength are harmful to the impact toughness of deposited metal of welding consumables,and only Ni and Mn elements are beneficial;in the post weld heat treatment process,the increase of tempering temperature is limited by the critical temperature AC1 of weld metal;reasonable adoption of welding process parameters(including operating techniques)is to refine the martensitic microstructure to a certain extent,thereby assisting in improving the toughness of the deposited metal.The toughness control principle of deposited metal of 9%Cr steel welding consumables,which aims to form fine martensite microstructure with low oxygen content and obtain full tempered martensite after post weld heat treatment,and control AC1 is not to be too low and has a specific and feasible implemen-tation scheme.It has been adopted by enterprises in the industry,and the control effect is remarkable.关键词
9%Cr钢/熔敷金属/韧性/焊接材料/准成分匹配Key words
9%Cr steel/deposited metal/toughness/welding consumable/quasi-composition matching分类
矿业与冶金
