Zr对Ti微合金化低碳钢形变奥氏体再结晶和析出相的影响

Effect of Zr on Deformed Austenite Recrystallization and Precipitates in Ti-Microalloyed Low Carbon Steel

通过多道次模拟压缩实验,研究不同Zr和Ti含量的三种Ti微合金化低碳钢在950℃~1050℃形变奥氏体再结晶和析出相的变化和最佳变形温度。结果表明,Ti含量的提高和Zr的加入使Ti微合金钢形变奥氏体的再结晶和晶粒长大延迟。Zr的加入还能增加Ti微合金钢中析出相的数量、改善析出相尺寸分布的均匀性进而得到相对均匀的奥氏体组织。变形温度为1000℃时的Ti-Zr微合金钢奥氏体组织最细小均匀。

The recrystallization and precipitates of deformed austenite for three Ti-microalloyed low carbon steels with different amount of Zr and Ti in the temperature range of 950°C to 1050°C were investigated by means of multi-pass compression test to simulate the actual rolling situation, in order to acquire the optimum deformation temperature for the alloys. The results show that the increase of Ti content will retard the occurrence of the recrystallization of deformed austenite and the recrystallization grain growth in Ti-microalloyed steels, while the addition of Zr will also retard the occurrence of recrystallization of deformed austenite in Ti-microalloy steel, and inhibit the growth of recrystallization grains. Besides, the addition of Zr increases the number of precipitates in Ti-microalloyed steel, and improves the size uniformity of precipitated phase, so that the Ti-Zr microalloyed steel consists of a relatively uniform austenite microstructure. When the deformation temperature is 1000℃, the Ti-Zr microalloyed steel has the finest uniform austenite microstructure.