湘钢ML40Cr钢线材表面混晶原因分析及控制

Analysis and Control of Mixed Crystal of ML40Cr at Xianggang

湘钢生产的ML40CrQ-1成品盘条奥氏体晶粒度难以满足客户需求,通过对成品盘条进行奥氏体晶粒度检测,确认ML40Cr成品盘条近表面部分区域存在混晶现象,混晶现象是由于钢中AlN分布不均匀造成。将钢中Al含量适当调低,控制初轧的终轧温度,提高钢轧加热温度和吐丝温度,有利于后期AlN均匀析出,减轻混晶现象。

The austenite grain size of the ML40CrQ-1 finished wire rod produced by Xiangang steel is difficult to meet the customer's needs.Through austenite grain size testing of the finished wire rod,it is confirmed that some areas near the surface of the ML40Cr finished wire rod have mixed grain phenomenon,which is caused by the uneven distribution of AlN in the steel.The content of Al in the steel was appropriately lowered,the final rolling temperature of the initial rolling was controlled,and the heating temperature and spinning temperature of the steel rolling were raised,which was conducive to the uniform precipitation of AlN in the later stage and the reduction of mixed crystal phenomenon.