316LN钢奥氏体晶粒长大模型

Study on austenite grain growth behavior of 316LN steel

通过改变加热温度和保温时间研究核电主管道用钢316LN奥氏体晶粒的长大规律。结果表明,随着加热温度的升高和保温时间的延长,实验钢奥氏体晶粒尺寸逐渐增大,且加热温度为1 200℃保温2h时出现混晶现象。奥氏体平均晶粒尺寸变化曲线表明,与保温时间相比,加热温度对晶粒尺寸的影响更大。对实验数据进行非线性回归,建立了描述316LN钢奥氏体晶粒长大规律的数学模型;通过对比实验值与计算值验证了模型的精度和可靠性。研究结果对确定316LN钢始锻温度和制订加热规范具有指导意义。

By changing heating temperature and holding time , the austenite grain growth behavior of 316LN steel was studied . The experimental results show that the austenite grain size increases with the increasing heating temperature and holding time , and the mixed grains are observed when the steel is heated to 1200℃ and held for 2 hours . As is shown in the curves of average grain size of austenite , the heating temperature has greater influence on the grain size than that by the holding temperature . The mathematic model for describing the grain growth behavior of 316LN steel was developed using non-linear regression ,and was validated through the comparison between the calculated values and the experimental ones . The study can theoretically contribute to the determination of 316LN steel＇s initial forging temperature and heating specification .