基于Workbench纤维增强扁挤压筒结构优化设计

Optimized design based on Workbench fiber reinforced flat extrusion cylinder struture

应力集中是导致扁挤压筒服役时的主要破坏方式,为降低扁挤压筒在挤压镁合金板材时产生的拉应力,构建了一种针对铝合金板材挤压模具优化模型,该模型在考虑扁挤压筒受预紧力及内压力作用下,通过改变相对过盈量、层间径比对扁挤压筒等效应力分布的影响,深入研究了扁挤压筒结构参数优化机理并给出了优化参数的选取范围;在优化后的材料应力集中位置取材并加入碳化硅纤维层,在此基础上,进行了有限元模拟分析。结果表明:当相对过盈量取0.27%、外套外径取440 mm、椭圆度取1.0时,取得了扁挤压筒服役时最佳应力分布;拉伸模拟测试之后发现屈服强度和抗拉强度均提高了11%左右。优化模型从结构和增材两方面同时提高了扁挤压筒的使用寿命,为进一步优化奠定了基础,使得镁合金板材扁挤压筒挤压条件更加完善。

Stress concentration is the main failure mode leading to the flat extrusion cylinder in service. In order to reduce the tensile stress generated by the flat extrusion cylinder during the extrusion of magnesium alloy sheet, an optimization model for the extrusion die of aluminum alloy sheet was constructed. Considering the preload and internal pressure on the flat extruding cylinder, the model studies the optimization mechanism of the structural parameters of flat extruding cylinder and gives the selection range of the optimization parameters by changing the influence of the relative interference and the interlayer diameter ratio on the equivalent stress distribution of the flat extruding cylinder.The test material was taken from the optimized stress concentration position and added with silicon carbide fiber layer, and simulated and analyzed by the finite element analysis software on this basis.The results show that the optimal stress distribution is obtained when the relative interference is 0.27%, the outer diameter of the jacket is 440 mm and the ovality is 1.0. Tensile simulation tests showed that the yield strength and tensile strength were improved by about 11%. The optimization model improves the service life of the flat extrusion cylinder from both structural and additive aspects, lays a foundation for further optimization, and makes the extrusion conditions of the flat extrusion cylinder of magnesium alloy sheet more perfect.