ZHENG Xiao, TAN Keli, DAI Hong. Research on microstructure and mechanical properties of linear friction welding joint of U20Mn rail steel[J]. 2020,50(11):64-70. DOI： 10.7512/j.issn.1001-2303.2020.11.12.
In view of the poor performance of flash welding and gas pressure welding joint of U20 Mn rail,linear friction welding was used to study the weldability of U20 Mn rail steel,and impact,tensile and metallographic tests were carried out to explore the mechanical properties and micros-tructure characteristics. The results show that the formation of U20 Mn linear friction welding joint is good and there is no defect found in the weld. The width of weld zone for as-welded joint is 4.88 ～5.69 mm,which can be divided into base metal zone（BM）,heat mechanical affected zone（HMAZ） and weld center zone（WZ）. After normalizing heat treatment,the microstructure of the joint is improved and tends to be consistent.The strength is 1 634 MPa（increased by 23.3%）,and the elongation is 10.0%（increased by 81.8%）.