Development Of Speed-raising Locomotive Axle Steel In Beiman Special Steel

Due to the strong exclusiveness of high speed railway transportation technology,high barriers to intellectual property rights,it is one of the main obstacle of the development of high-speed railway in our country.To break the foreign technology monopoly,to realize high speed axle localization for the design of domestic high speed axle steel material research and development.Based on the analysis to study the foreign material on the basis of the research and design a suitable for domestic high speed axle EA4T steel material composition,the carbon content is 0.23%?0.28%,silicon content is 0.17%?0.38%,manganese content 0.53?0.53%,chromium content is 0.95%?1.15%,0.16%?0.29%molybdenum content,niobium content 0.02%?0.02%,the aluminum content is 0.02%?0.05%,supplemented by a small amount of micro alloying elements such as copper,vanadium,nickel.Determine the high-speed axle of EA4T steel production process,the use of converter steel making,supplemented by LF refining furnace,RH vacuum degassing treatment,by the caster casting into great circle casting billet,then through forging into axle billet.Forging heating insulation temperature control at 1280? or so,can eliminate the production of mixed crystal,and remove the billet surface crack;For the trial production of high-speed axle EA4T steel inspection,macrostructure,non-metallic inclusions,grain size,organization and mechanical properties of the army in accordance with science and technology letter[2013]no.49 of the 200?250 km/h emu with axle manufacture technology conditions(provisional)"of the corresponding requirementsBeiMan special steel co.,LTD provides EA4T material by Shanxi the orthometric iron technology co.,LTD.,processed into high-speed axle,through the course of fatigue test and the axial fatigue test.Determine the small sample of EA4T axle material rotating bending fatigue limit strength is RfL=403 mpa(smooth specimens),RfE=365 mpa(notch specimen),meet the EN 13261 standard for small sample axle fatigue 3.2.3 provisions of the requirements of the ultimate strength(EN 13261 standards RfL acuity 250 mpa,RfE 170 mpa or higher).The whole shaft fatigue test a total of 10 million times,through detailed crack magnetic particle inspection and ultrasonic inspection found,conducted by the axle fatigue test.