奥氏体贫碳区性质与贝氏体相变热力学SCIEI

奥氏体内贫碳区可分为三类,即平衡贫碳区、非平衡贫碳区及随机贫碳区,分析计算了各类贫碳区内奥氏体转变为同成分铁素体的相变化学驱动力,根据奥氏体贫碳区内贝氏体切变转变机制计算了贝氏体相变开始温度B_s,3％Cr钢和CrMo钢在其B_S温度可获得的最大相变驱动力。在整个贝氏体相变温区,贝氏体铁素体以部分过饱和碳量切变形成的构想在热力学上是可能的。

CHARACTER OF CARBON DEPLETED REGIONS IN UNDERCOOLED AUSTENITE AND THERMODYNAMICS OF BAINITIC TRANSFORMATION

The chemical driving forces for the phase transformation from auste-nite in three different carbon depleted regions into ferrite with identical composi-tion have been derived respectively. The starting temperature of bainitic transform-ation, B_s, has been also calculated according to the shearing mechanism of baini-tic transformation in the carbon depleted regions of austenite. The maximum driv-ing forces for the phase transformation in both 3%Cr containing and CrMo steelsmay be obtained at temperature B_s. It was shown that the proposal of the shearingmechanism of the bainitic transformation is thermodynamically possible.