奥氏体化温度对奥氏体晶粒度及第二相固溶的影响

Effect of austenitizing temperature on size of austenite grain and solid solution of second phase particles

利用光学显微镜等研究了SA516Gr60N容器钢在不同奥氏体化温度下奥氏体晶粒尺寸的长大规律以及微合金元素Nb、Ti、V的固溶规律。研究结果表明,随着奥氏体化温度的升高,微合金元素Nb、Ti、V的固溶量逐渐增加;990-1 050℃时,原始奥氏体晶粒尺寸增加缓慢,晶粒细小均匀;1 070℃时晶粒出现异常长大现象,随后部分奥氏体晶粒急剧长大,不均匀性越来越明显;1 170-1 210℃时,奥氏体晶粒尺寸均匀化。

Growth behavior of austenite grain and solid solution rules of microalloyed elements（Nb,Ti and V）in SA516Gr60 Nvessel steel at different austenitizing temperatures were studied with metallographic microscopy.The results show that with the increase of austenitizing temperature,the amounts of solid solution of the microalloyed elements（Nb,Ti and V）gradually increase.When austenitizing temperature is 990-1 050℃,size of original austenite grain increases slowly and the grains are small and homogeneous.When austenitizing temperature is1 070℃,most of austenite grains grow up rapidly with obvious heterogeneity.When austenitizing temperature is1 170-1 210℃,austenitic grain size becomes uniform with increasing austenitizing temperature.