含钼低碳微合金化钢连续冷却过程相变动力学研究

在热模拟试验机上采用膨胀法并结合金相组织观察，测定了含钼和不含钼的试验钢贝氏体转变CCT曲线。研究了超低碳微合金化钢中钼元素对形变奥氏体连续冷却转变过程相变动力学的影响，结果表明，钢中加入ω（Mo）0．4％后，明显降低贝氏体的析出温度，并得到更细小的贝氏体组织；同时在相同的冷速条件下形成的M（马氏体）岛状组织也更加细小弥散；形变奥氏体在连续冷却过程中即使在冷速较低情况下也能获得细小的贝氏体组织。

Study on kinetics of phase transformation in the process of continuous cooling for Mo bearing low carbon micro-alloyed steel

The CCT curve of the bainite transformation of the Mo bearing and Mo free trial steel has been measured and the metallographic structure of the steels observed by expansion method in a thermo-sirnulation machine. The effect of Molybdenum element in the extra low carbon micro-alloyed steel on the kinetics of phase transformation of the transformed Austenite in the process of continuous cooling transformation has been studied. Results show that the precipitate temperature for the hainite apparently dropped down and finer bainite structure appeared as soon as 0.4% Molybdenum was added in the steel and in the meanwhile the island-shaped Martensite structures occurring in the similar cooling speed were even finer and diffused. The Austenite can be transformed into fine Bainite even if the cooling speed is relatively lower in the process of continuous cooling.