摘要
用定量金相法研究了30Cr2Ni4MoV低压转子钢在不同原奥氏体晶粒度条件下(1.0级与6.0级)以30℃/h加热至840℃保温10 h后过冷奥氏体在不同等温温度(575、600、625℃)下珠光体转变量与等温时间的关系。根据试验结果拟合得到表征珠光体转变动力学的Avrami方程,进而绘制了分别适用于低压转子锻后热处理与性能热处理的30Cr2Ni4MoV钢珠光体等温转变的时间-温度-转变量曲线(TTT曲线)。在拟合得到考虑原奥氏体晶粒度因素的修正Avrami方程的基础上,比较了不同的原奥氏体晶粒度对珠光体转变的影响。
Austenite-pearlite transformation of 30Cr2Ni4MoV steel for low pressure （LP） rotors of steam turbine was investigated. The relationships between the transformed volume fraction of pearlite and the isothermal holding time at different temperatures （ 575 ℃ , 600 ℃ and 625 ℃ ） and in different prior austenite grain sizes （ ASTM no. 1.0 and ASTM no. 6.0） were measured after austenitization at 840 ℃ for 10 h by quantitative metallographic method. Avrami equation describing the pearlite transformation kinetics was obtained by fitting the experimental result, and then the time-temperature transformation diagrams （TIT diagrams ） of isothermal pearlite transformation for 30Cr2Ni4MoV steel were also developed for the heat treatment after forging and for the quenching and tempering of LP rotors, respectively. Based on fitting modified Avrami equation with prior austenite grain size considered, the influence of different prior austenite grain sizes on the pearlite transformation was compared.
出处
《金属热处理》
CAS
CSCD
北大核心
2012年第5期1-5,共5页
Heat Treatment of Metals
基金
国家重点基础研究发展计划("973"计划)(2011CB012904)
上海市重大科技攻关项目(08DZ1100302)
上海市重点科技攻关项目(09521101303)
