变温度场下楔横轧端头凹心数值模拟研究

目的研究楔横轧凹心产生的原因以及变温度场对端面凹心的影响。方法采用数值模拟的方法,详细分析了楔横轧变形规律下凹心产生的原因。同时利用Deform-3D用户子程序方式,给轧件端部添加一定形式的变温度场,分析了变温度场改善凹心缺陷的机制;研究了变温区表面温度与变温度场长度对凹心深度的影响。结果楔横轧凹心是由轧至极限料头长度Imin时,端面金属变形不均匀引起的,凹心深度随着变温长度的增加和变温区表面温度的减小而减小,结论所提变温度场楔横轧轧制工艺,可以有效改善端面变形的均匀性,添加此变温度场可以有效减小楔横轧凹心深度。

Numerical Simulation Study on Cross Wedge Rolling End Concavity under Non-uniform Temperature Field

The aim of this work was to study the generation mechanism of cross wedge rolling ( CWR) end concavity and the influence of non-uniform temperature filed on the end concavity. The generation mechanism of end concavity under the deformation rule of cross wedge rolling was detailed analyzed with numerical simulation. Meanwhile, by adding a certain form of non-uniform temperature field on the billet end through Deform-3D software user-routine method, the mechanism that the non-uniform temperature field decreases the depth of the end concavity was analyzed. The influences of the billet surface temperature and the length of the non-uniform temperature area on the depth of end concavity were studied. The results showed that the end concavity was caused by the uneven metal deformation in the end face when the CWR mod- ule rolled to the critical end length Imin. The depth of the end concavity decreased with the increase of the length of the nonuniform temperature area and the decrease of the billet surface temperature. The CWR process under non-uniform temperature field mentioned in this paper could effectively improve the uniformity of the deformation of billet end. Therefore, the CWR's end concavity could be effectively decreased through adding non-uniform temperature field.