回火温度对高速重载列车车轴用钢EA4T冲击韧度的影响

Influence of Tempering Temperature on Impact Toughness of Axle Steel EA4T in High-speed Overloaded Trains

将经过不同温度回火后的EA4T钢试样分别加工成夏比V型和U型缺口冲击试样,通过系列冲击试验对EA4T钢的回火脆性进行了研究。结果表明,EA4T钢冲击韧度随回火温度的升高而升高,在550℃左右回火具有高温回火脆性,在高于回火脆性温度区回火时,其冲击韧度将大幅度提高。回火脆性对夏比V尖锐缺口的敏感性更高。

Preparing Charpy V and U type impact samples of steel EA4T tempered at different temperature, respectively, the temper brittleness of steel EA4T was researched by a series of impact test on above samples. The results show that, with the increase of tempering temperature, impact toughness of steel EA4T rises, and there is high-temperature tempering brittleness at about 550 ℃. When the tempering temperature is higher than the region of temperature, the impact toughness value will improve greatly. Also found Charpy V type samples have higher sensitivity than U type impact samples for tempering brittleness.