胀断连杆用中碳非调质钢的连续冷却转变

Continuous Cooling Transformation of Medium-carbon Steel for Fracture Splitting Connecting Rods

通过Gleeble-3800热模拟机,研究了一种胀断连杆用中碳非调质钢的连续冷却转变组织变化规律,分析了冷却速度对转变组织和显微硬度的影响.结果表明,当冷却速度为0.1~3℃/s时,组织为铁素体+珠光体,当冷却速度大于5℃/s时,开始发生贝氏体转变,随着冷却速度提高,贝氏体含量增多,并在速度大于15℃/s时发生马氏体转变.实验钢的显微硬度随着冷却速度的提高而增加.

Microstructure evolution of medium-carbon steel for fracture splitting connecting rod was evaluated using the Gleeble-3800 thermal simulation machine.The effects of cooling rate on the microstructure and micro-hardness of the medium-carbon steel were analyzed.The result shows that the microstructure of the steel is ferrite-pearlite with a cooling rate from 0.1℃/s to 3℃/s.Bainite transformation occurs when the cooling rate is greater than 5℃/s,and more Bainite can be observed with the increasing of cooling rate.Furthermore,Martensitic transformation will occur when the cooling rate is higher than 15℃/s.Micro-hardness of the experimental steel increases with the increasing of cooling rate.