E级铸钢制铁路货车车钩淬火加热时间研究

Study on Duration of Heating for Hardening Railway Freight Train Coupler of E-grade Cast Steel

铁路货车的车钩材料为E级铸钢,要求进行调质处理,淬火加热设备为专用悬挂式连续热处理炉。目前,车钩的淬火加热时间按每25mm最大截面厚度保温1h计算,这是否科学合理尚不清楚。为此,对车钩的淬火加热时间进行了实验室试验和现场试验,并检测了车钩的显微组织和力学性能。试验结果表明:车钩每25mm最大截面厚度保温1h的淬火加热时间偏长,更合适的淬火加热时间为145min。

Railway freight train couplers,made from E-grade cast steel,need to be quenched and high tempered,and their heating for hardening are carried out in a special continuous suspension-type heat treatment furnace.At the present,the couple is hold at austenitizing temperature for a period of 1 h per 25 mm of maximum section thickness,whether this is scientifically sound is not yet clear.For this reason,the couplers were tested for duration of heating for hardening in a laboratory and in working place,as well as for their microstructure and mechanical properties.The results demonstrated that the duration of heating for hardening of 1 h per 25 mm of maximum section thickness is too long,and it is preferable to hold for 145 min at austenitizing temperature,for the couplers.