为了探索楔横轧展宽长度和极限断面收缩率的关系,并进一步揭示其影响机理,做了不同展宽长度下的极限面收缩率实验,并利用有限元数值方法对典型工况展宽阶段轧制接触区温度变化情况进行了模拟,进而推导出展宽过程中轧制接触区变形抗力的变化情况,并采用轧制实验中测得的力能参数做了验证.得到展宽长度越大,可获得的极限断面收缩率越小的原因为:展宽变形时间变长,轧件轧制接触区温度下降,从而使变形抗力增大,轧件杆部横截面所受轴向应力随之增大,导致轧件杆部较容易发生缩颈.
In order to explore the relationship between spread width and limit-section shrinkage,and reveal the principle of it,limit-section shrinkage experiment is performed under distinct spread widths,then finite element method is adopted to simulate the typical working conditions' temperature on their working contact zone,and then the trend of deformation resistance on the contact zone is deduced. The reason is that as spread width is bigger,the time of stretching stage raises,temperature of the contact zone decreases,deformation resistance of the contact zone goes up,so axial stress on the intersecting surface of workpiece's shaft increases and easier leads to the workpiece shaft's having section shrinkage.