擠製加工是對裝入盛錠筒內的胚料施加壓力，使胚料經過所設計的模孔處流出，而成形為所需之形狀，如棒、管及線形等產品，為金屬成形的主要加工法之一，具有低成本，生產效率高，良好擠製品性質，強度高，模具壽命長，易於自動化生產之優點，故極具產業應用上之價值。本文利用有限元素分析軟體模擬分析活塞桿的擠製過程，分析鋁材不同之胚料厚度、模口角度、摩擦係數的參數來探討其對成形力與最後完工高度的影響，其次用不同實心胚料在模穴之成形力影響。

Extrusion is one of the most important metal forming processes due to its low cost, high productivity, satisfactory properties obtained for the extruded products, strength is high, die life is lengthways and easy to the automating the production, so have the value on the industry application. In this paper, a finite element analysis software DEFORM-2D is used to investigate the autocar piston rod extrusion through an axi-symmetric die. The analytical aluminum material is different of the workpiece thickness, mold port angle, friction coefficient the influences of the parameters to inquire into it to the forming force and finally complete work the high influence and the different solid workpiece to effect in the forming force of the cavity.