论文部分内容阅读
设计研发了以Mn-Ni-Mo合金为主的低温管线用埋弧焊丝。实际K65管线钢平板焊接实验结果显示,焊缝金属屈服强度可达552~658 MPa,抗拉强度可达677~764 MPa,总延伸率和面缩率可达22%和70%以上,且-40℃冲击功均可达120 J。焊缝组织为精细的针状铁素体和少量侧板条铁素体,且含有少量弥散分布的细小M/A(马氏体/奥氏体岛)。此外,研究发现Mo含量的适量增加可显著降低侧板条铁素体含量。保证焊缝金属具有0.2%左右的Mo,同时适量增加Mn和Ni,可使焊缝金属获得优异的力学性能。
Design and development of Mn-Ni-Mo alloy-based low temperature pipeline with submerged arc welding wire. The actual K65 pipeline steel plate welding experimental results show that the weld metal yield strength up to 552 ~ 658 MPa, the tensile strength of up to 677 ~ 764 MPa, the total elongation and reduction of surface area up to 22% and 70%, and - 40 ℃ impact energy up to 120 J. Weld microstructure of fine acicular ferrite and a small amount of side strip ferrite, and contains a small amount of dispersed fine M / A (martensite / austenitic island). In addition, the study found that the moderate increase in Mo content can significantly reduce the side strip ferrite content. To ensure that the weld metal has about 0.2% Mo, while increasing the amount of Mn and Ni, the weld metal can obtain excellent mechanical properties.