钢轨固定式闪光焊接头力学性能分析

Mechanical Performance Analysis of Stationary Rail Flash Welding Joints

钢轨固定式闪光焊接头是我国无缝线路接头的主要形式。本文通过系统的取样试验,分析了U71Mn和U75V热轧和热处理钢轨焊接接头不同部位和全断面不同位置的冲击、拉伸和硬度性能。试验结果表明:钢轨固定式闪光焊接头的冲击功平均值是离散分布的,轨头冲击功明显大于轨底,轨腰最小;相同牌号和交货状态的钢轨,接头全断面不同位置的抗拉强度相差不大;同牌号钢轨,热处理接头轨腰部位伸长率明显小于热轧钢轨;热轧钢轨焊接接头硬度一般大于钢轨母材硬度,热处理钢轨则相反。

The stationary rail flash welding joint is the main joint form of the continuous welding rail in China. In this paper, the impact, tensile and hardness performance of U71Mn and U75V hot-rolled and heat-treated rail welding joints at different parts and full-section locations was analyzed by systematic sampling test. The results show that the average impact energy of the stationary rail flash welding joints is discrete, and the impact energy of the rail head is obviously larger than that of the rail bottom, and the impact energy of the rail waist is the smallest. For rails with the same grade and delivery status, the tensile strength of different full-section locations of joints is not much different. For rails with the same grade, the elongation of waist part of the heat-treated joints is significantly smaller than that of the hot-rolled rail. The hardness of welding joints of the hot-rolled rail is generally greater than the hardness of the rail base,but the heat-treated rail is the opposite.