核电SA508-3钢奥氏体晶粒长大规律的研究

利用箱式电阻炉对SA508-3钢进行了不同条件下的加热保温实验,分别讨论了加热温度及保温时间对奥氏体晶粒长大的影响。实验结果表明:MC型化合物的溶解温度大约处于1050~1100℃之间。当保温时间恒定,温度低于1050℃时,晶粒生长缓慢,随温度的升高,生长速率增大。保温温度恒定时,在保温初期晶粒急剧长大,随保温时间的延长,晶粒长大趋势趋于平缓。在此基础上,建立了SA508-3钢奥氏体晶粒长大数学模型。

Research on Austenite Grain Growth Behavior of Nuclear Power SA508-3 Steel

By using the chamber type electric resistance furnace, the heating and thermal insulation tests of SA508-3 steel have been performed in different conditions.The influence of heating temperature and holding time on austenite grain growth has been discussed respectively.The results show that the solution temperature of MC type chemical compound is about in the range of 1050~1100 ℃.When the temperature is lower than 1050℃ and the holding temperature is constant, the growth of grain is slow, and the growth rate increases with temperature rising.When the holding temperature is constant, the grain suddenly grows at the beginning of holding stage.The trend of grain growth becomes flat with the holding time.On this basis, the mathematical model of austenite grain growth of SA508-3 steel has been built.