Fe-6.5%Si轧制板材热处理制度工艺的优化

OPTIMIZATION OF HEAT TREATMENT PROCESS OF Fe-6.5%Si SHEET

研究了热轧Fe-6.5%Si(质量分数)高硅钢薄板在不同温度、不同时间的热处理条件下其组织及合金力学性能的变化.结果表明,经过热处理的试样具有更好的力学性能,300℃拉伸延伸率比热轧态试样的延伸率(9.09%)高出近1倍,硬度也大幅下降,有利于后续轧制的进行.通过对比分析,确定在850℃下保温1 min并在盐水中淬火是较理想的热处理条件,在此条件下处理的Fe-6.5%Si合金板材组织均匀,塑性提高,硬度降低,有利于下一步轧制的进行,并且该条件也大大提高了现有的热处理效率,满足生产工艺的要求.

Fe-6.5%Si （mass fraction） alloy exhibits excellent soft magnetic properties and there- fore is very suitable to be used as iron core in high frequency electromotor. However, the room- temperature embrittlement and poor workability limit the practical applications of the alloy and it is hard to be fabricated to thin sheet. It is reported that ultra-thin sheet with 0.05 mm in thickness has been successfully obtained by an advanced technique of stepwise ductilization, including hot, warm and cold rolling processes with intermediate heat treatment. And suitable heat treatment can improve the ductility of this alloy sheet, therefore it plays an important role in this technique. However, the existing heat treatment is time consuming and not suitable for industry. In this work, effects of heat treatment on mechanical properties of the hot-rolled sheet have been investigated in dependence of annealing temperature and time. The experimental results show that heat treated Fe-6.5%Si sheets have better mechanical properties than those of as hot-rolled sheets. Elongation of heat treated sample is twice as hot-rolled sample＇s and hardness decreases significantly. Also it is found that heat treatment at 850 ℃ for 1 min and then quenching in brine provides good ductility and low hardness, which is benefit to the subsequent processes and increases the productivity substantially.