热轧辊冷却对冷轧无取向电工钢卷纵向磁性的影响及工艺优化

通过对35W300高牌号0.35 mm冷轧无取向电工钢卷(/%:0.002C、2.71Si、0.22Mn、0.015P、0.003S、0.0020N、0.55Als)头、中、尾组织、织构及对应的磁性能的试验研究,发现因热轧时12 MPa高压水连续冷却造成接触轧辊的钢卷头、中、尾在不同温度下轧制,卷取后钢卷头部处于卷心、温度略高而冷却速度略低于钢卷尾部,致使钢卷纵向组织、织构不同,成品卷头、尾各250 m内磁感逐渐增加,铁损逐渐降低,250 m外至钢卷中部磁性能稳定。通过将热轧辊的冷却方式改为周期冷却和卷取后的层流冷却改为钢卷70 m后开始冷却,至钢卷尾部70 m前停止冷却的方式使得钢卷纵向铁损差异明显减小,磁感差异略有改善。

Effect of Hot Roller Cooling on Magnetic Properties of Longitudinal Strip Coil of Cold Rolled Non-oriented Electrical Steel and Process Optimization

According to the test research on structure and texture of head, meddle and end of 35W300 high grade 0.35 mm cold rolled non-oriented electrical steel strip coil (/% : 0.002C, 2.71Si, 0.22Mn, 0.015P, 0.003S, 0.0020N, 0.55Als) and corresponding magnetic properties, It is found that due to 12 MPa high pressure water continuous cooling the roller in hot rolling process led to head, middle and tail of strip rolling at different temperature and after coiling the head of strip coil being in center of coil led to its temperature slightly higher and cooling speed lower than that of tail of coil, as a result the longitudinal structure and texture of coil are different and the magnetic induction gradually increases and iron loss gradually decreases in 250 m at head and tail, more than 250 m to middle of coil the magnetic properties are stable. With modifying the hot roller continuous cooling model to cycle cooling model and modifying the laminar cooling model after coiling to starting cooling after coiling 70 m and stopping cooling ahead 70 m of finishing coiling, the difference of iron loss of longitudinal coil obviously decreases and the difference of magnetic induction slightly improves.