关键词: 60E1A1-60E1尖轨跟端, 热处理, 工艺优化, 组织, 性能

Abstract: 60E1A1-60E1 switch rail heel end made with R350HT steel AT rail was treated by full section induction heating+blowing heat treatment. The effects of raw material, heating temperature and blowing position on the microstructure and properties of the switch rail heel end were analyzed. The results show that when there is a large amount of grain boundary ferrite in the raw material, there will still be obvious grain boundary ferrite after forging heat treatment, which leads to the decrease of hardness and elongation of the heel end of the switch rail. When the heating temperature is lower, the martensite content is higher after the heel forging heat treatment, and the hardness of both the top surface and the cross section is higher, but the elongation is reduced. Under the condition of multi-wind box blowing, the transition section and the forming section should be completely placed in the low wind pressure area as far as possible. By controlling the quality of the raw material, adjusting the heating temperature to 930 ℃, and placing the heel end transition section under a single air box, a switch rail heel end product with a strength of more than 1200 MPa, an elongation of more than 10%, and both the top surface hardness and section hardness meeting European standards can be produced.

Key words: 60E1A1-60E1 switch rail heel end, heat treatment, process optimization, microstructure, mechanical properties