论文部分内容阅读
通过单道次压缩变形热模拟试验,研究微合金钢加热到两相区变形时的组织演变规律,并分析加热温度对其的影响。使用OM、SEM和EBSD分析试验钢的微观组织和取向分布。结果表明,加热后奥氏体相变在晶界上发生,740~800℃时奥氏体体积分数为20%左右,830℃时奥氏体体积分数大幅增加到50%。加热到两相区变形时,形变铁素体发生动态回复或动态再结晶,随变形温度增加,形变铁素体由动态回复向动态再结晶发展,亚晶界减少,830℃时大角度晶界比例达到91.2%,冷却后得到均匀的细晶组织,平均有效晶粒直径3.9μm。
Through single-pass compression deformation thermal simulation test, the microstructure evolution of the microalloyed steel heated to the deformation of the two-phase zone was studied, and the influence of heating temperature on it was analyzed. OM, SEM and EBSD were used to analyze the microstructure and orientation distribution of the test steel. The results show that austenite transformation takes place at the grain boundary after heating. The volume fraction of austenite at 740-800 ℃ is about 20%, and the volume fraction of austenite at 830 ℃ increases sharply to 50%. When heated to the deformation of the two-phase zone, the deformed ferrite undergoes dynamic recovery or dynamic recrystallization. With the increase of the deformation temperature, the deformed ferrite changes from dynamic recovery to dynamic recrystallization, and the subgrain decreases. At 830 ℃, The proportion reached 91.2%, after cooling to obtain a uniform fine grain structure, the average effective grain diameter 3.9μm.