内磁屏蔽钢再结晶软化曲线拟合与组织分析

Analysis on Recrystallization Softening Curve and Microstructure of Inter-Magnetic Shielded Steel

试验测试和观察了不同卷曲温度下生产的内磁屏蔽钢带的显微组织和硬度,并对硬度数据按Boltzmann函数模型拟合静态再结晶软化曲线,从而求得静态再结晶温度为628℃左右;在高于静态再结晶温度的卷曲温度下,热变形组织得到明显改善,不同方向晶粒尺寸非常接近,这进一步证实曲线拟合所得结果的可靠性;在680℃卷曲温度下轧向与板向组织晶粒平均尺寸分别为65.4μm和66.9μm,尾部组织与头部的相比存在较多未长大的形核晶粒。

The microhardness and microstructure of inter-magnetic shielded steel strips were measured under different curl temperature. According to results of microhardness, the curvilinear equation of microhardness and curl temperature was obtained, and the static recrystallization temperature that is measured on the equation is about 628℃. while the curl temperature was higher than Tr, the microstructure under hot rolling is obviously improved and the grains are of close size in different sections. Thus the reliability of Tr is confirmed. With 680℃ curl temperature, the average grain size is 65.4 μm in cross-section and 66.9 μm in face-section, there is more small-sized nucleated grains in rear site than that in head site of the strip.