摘要
借助X射线衍射分析、金相组织观察研究了9 SiCr奥氏体化后的冷却速度与等温保温时间对下贝氏体相变产物的形貌、相组成和晶格常数的影响。实验结果表明,当奥氏体化后的冷却速度接近临界冷速(60℃/s)、等温时间大于孕育期(80 s)且在20 min以内短时等温获得非常规下贝氏体组织,其光学显微组织形态呈现由单一α相组成的短针状,晶格常数和平衡态α相不同,其值为2.874,呈现晶格膨胀状,具有马氏体转变特征。
The effects of cooling speed after austenitization and isothermal time on the morphology, the phase composition and the lattice constant in the products of bainite transformation in 9SiCr steel have been studied by the X- Ray diffraction pattern analysis and optical microscope. The experimental results show that only when the following conditions which are fast cooling after austenitization and isothermal time from 80 s to 1200 s are provided can the irregular low bainite be obtained. And it is made of monophase a, its shape is short needle shape, the lattice is expanded with lattice constant a = 2. 874. Therefore, its formation feature has the characteristics as martensite mechanism.
出处
《热处理技术与装备》
2007年第5期24-27,共4页
Heat Treatment Technology and Equipment
