Abstract:Research purposes:At present,the annual traffic volume of the heavy - haul railway in China has been approach to 500 million tons.Using the laser surface engineering technology to improve the wheel /rail relationship and prolong the rail overhaul interval has already become a pressing task. Nowadays,in this field,the laboratory test and the on-site research and application in China mainly include the laser transformation hardening technology and laser cladding technology have been more frequently used,while there is little information on the laser glazing technology and its application in glazing the wheel /rail surface.This paper in detail introduces the research on the laser glazing rail test in FAST at TTC and its ex-post analysis report announced by the office of federal railway administration in May 2007for the purpose of giving the reference to domestic researchers.
Research conclusions:(1) The reason for failure of laser glazing rail is the continuous extension of cracks induced by laser glazing in fatigue conditions.(2) The laser re - melting overlapping zone is the most sensitive area where the residual stresses promote crack formation and spreading.(3) The laser glazing rails must undergo a complete metallurgical evaluation to determine their integrity before installation on track.
[1]U. S. Department of Transportation Federal Railroad Administration Office of Research and Development.In-Track Demonstration of Laser - Treated Rail to Reduce Friction and Wear[R].Springfield: National Technical Information Service,May 2007: 1 - 68.
[2]张准胜,吕杰胜,袁明振. 一种激光表面熔凝的铁道钢轨[P].中国: ZL01219892.7,2002-01-30 Zhang Zhunsheng,Lv Jiesheng,Yuan Mingzhen.A Kind of Laser Surface Glazing Railway Rail[P].China:ZL01219892. 7,2002-01-30
[3]郑州铁路局新乡工务段. 国铁1/12 提速道岔激光相变硬化直护轨试验报告[R]. 河南新乡: 郑州铁路局新乡工务段,2002. Zhengzhou Railway Department Xinxiang Track Division. The Manufacture and Laying of Laser Transformation Hardening Turnout Straight Guard Rail[R].Xinxiang: Zhengzhou Railway Department Xinxiang Track Division,November 2002.
[4]尹维一. 应用激光相变硬化工艺技术提高尖轨使用寿命[J].冶金设备管理与维修,2003( 6) :47 -48. Yin Weiyi. Application of Laser Transformation Hardening Technology to Improve the Tongue Rail Service Life[J]. Metallurgical Equipment Management and Maintenance,2003( 6) : 47 - 48.
[5]济南铁路局工务器材段. 激光淬火提速道岔曲尖轨和护轨研制报告[R]. 济南: 济南铁路局工务器材段,2004. Jinan Railway Department Work Equipment Maintenance and Repair Shop. Laser Quenching Turnout Tongue Rail and Guard Rail Research Report [R]. Jinan: Jinan Railway Department Work Equipment Maintenance and Repair Shop,2004.
[6] 张准胜,吕杰胜,铁路轨道激光维修车[P]. 中国:ZL02100096.4,2006-12-20. Zhang Zhunsheng,Lv Jiesheng.Railway Track Laser Maintenance Car [P]. China: ZL02100096. 4,2006 -12 -20.
[7]杨胶溪,刘华东. U71Mn 钢轨表面激光融覆 Fe 基合金组织与性能研究[J]. 铁道工程学报,2010( 7) :34 -37. Yang Jiaoxi, Liu Huadong. Research on the Microstructure and Properties of Laser Cladding Fe-based Alloy on U71Mn Rail Surface[J]. Journal of Railway Engineering Society,2010( 7) : 34-37.
[8] 郭战伟. 大秦重载铁路大修换轨周期的探讨[J]. 铁道建筑,2011( 11) :106 -109. Guo Zhanwei.Discussion on Da-Qin Heavy Haul Railway Overhaul in Rail Cycle [J].RailwayConstruction,2011( 11) : 106 - 109.