低碳贝氏体钢中温转变热模拟试验

Thermal Simulation Experiment on Intermediate Transformation Behavior of Low-carbon Bainitic Steel

研究了一种Mn-Nb低碳贝氏体钢。通过热模拟试验,测定试验钢的相变点温度并绘制其静态CCT曲线,研究试验钢在不同冷速下显微组织及显微硬度的变化规律。在所研究的冷却速度范围内,冷速越高,相变开始温度越低,随着冷速的增加贝氏体钢的显微组织由粒状贝氏体逐渐转变为板条贝氏体,且板条束越来越细小,硬度越高。

A low-carbon bainitic steel of Mn-Nb system is studied in this paper. Thermal simuhtion experiment is conducted to determine the phase transformation point temperature of testing steels and draw its static CCT curve, and microstructure and microhardness changes in different cooling rate are also studied. In the studied range of cooling rate, the higher the cooling rate, the lower phase transformation point temperature. And with the increase of coling rate, Iminite microstrueture changes from granular bainite to lath bainite. Lath is becoming smaller with higher microhardness.