Cct Diagram Determination And Characteristics Microstructure Analysis Of Heat Treatment Process Of The Heavy-rail End

Strengthening heat treatment of heavy rail can not only improve the quality and enhance the service life of heavy rail, heavy rail is also the inevitable trend of development. Combination of rail service conditions and performance requirements of the heavy rail steel heat treatment process characteristics.The large-scale production plants were selected and Wuhan heavy rail U71Mn rail, combined with thermal expansion method and metallographic method, by Gleeble-1500 thermal simulation testing machine to test on the sample: the sample heated to austenitizing and quenching after homogenization ; determination of different heating temperature and cooling conditions are the expansion of the data; use cooling + tempering simulation for on-site production of heat treatment.Using electron microscopy and optical microscopy sample at austenitizing temperature after quenching to retain the organization; using Origin software transformation of undercooled austenite in continuous cooling curve drawn on the tissue samples tested at room temperature and cooling rate on the sum specified steel grades starting temperature, phase transition and organizational speed and hardness of law; field produced by simulating the heat treatment process, provide the theoretical basis for the site.U71Mn steel through the continuous cooling transformation of the organization, performance and the relationship between process parameters, combined with rail service conditions and performance requirements, further testing of the continuous changes in the law of steel, process parameters on the nature of change and organizational impact of the steel kinds of heat treatment system to provide a basis for the development.