大高径比ZA27合金铸件挤压铸造应力场模拟

Stress field simulation of ZA27 alloy casting with larger ratio of height to diameter during squeeze cast

大高径比挤压铸件成形时的一个显著特征是压力沿着轴向分布严重不均.作为挤压铸造中的一个重要参数,比压严重影响铸件的组织和性能.利用有限元法对大高径比ZA27合金柱形挤压铸件凝固过程中的压力分布进行了热力耦合数值模拟,分析了铸件比压与显微组织和力学性能的关系.通过改变铸件与模具之间的摩擦系数、高径比,对铸件内部比压分布进行了数值模拟,讨论了工艺参数对比压力分布的影响情况,取得了令人满意的结果.

The distinct characteristic of squeeze casting with larger ratio of height to diameter is (heterogenous) distribution of squeeze pressure.As an important technical parameter during squeeze cast,the specific pressure has great influence on microstructure and mechanical property of the castings.In this (paper,)the pressure field of the ZA27 alloy squeeze casting with considerable ratio of height to diameter was simulated coupled with temperature field by the FEM simulation program and the influence of pressure on microstructure and mechanical property was analyzed.The simulation of pressure field was done by altering friction coefficient and ratio of height to diameter.The results are quite satisfactory.