摘要
利用KRC模型对焊缝金属中针状铁素体转变的热力学驱动力进行了理论计算。计算结果表明,焊缝金属中AF(针状铁素体 )相变开始温度的理论值为 1 100K(827℃)。试验所测得的焊缝金属中针状铁素体转变开始温度实际值为 670℃, 针状铁素体的相变热力学驱动力数值为ΔGγAF+γ1≤ -570J/mol。随着转变温度的降低和焊缝金属中碳含量的降低,针状铁素体的形核和长大驱动力增加。针状铁素体的总相变驱动力小于其形核和长大的驱动力,这种差距随转变温度的降低而增大。
The thermodynamics driving force of acicular ferrite (AF) transformation was calculated in theory using the model of KRC (Kaufman, Radcliffe, Cohen). The calculated result showed that the theoretical value of the starting temperature of AF transformation in weld metal was 1100 K (827°C). And the actual value of the starting temperature of AF transformation in weld metal was 943 K (670°C). The theoretical value of the driving force of AF transformation in weld metal was less than -570 J/mol. The driving force of AF nucleation and growth increased with the decreasing of AF transformation temperature and the carbon content in weld metal. The total driving force for AF transformation was smaller than that of AF nucleation and growth. And the difference increased with the decreasing of AF transformation temperature.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2005年第1期12-16,共5页
Transactions of The China Welding Institution
基金
国家重点基础研究发展规划项目(973项目)(1998061500)
关键词
微合金钢
焊缝组织
针状铁素体
驱动力
Austenitic transformations
Crystallization
Nucleation
Steel metallography
Welded steel structures
