轴对称超塑充模胀形有限元模拟

采用大变形刚粘塑性有限元法首次模拟研究了考虑空洞效应的超塑充模胀形过程，模具为轴对称任意倾角锥形模（含直壁圆筒）。采用修正的Ｌａ－ｇｒａｎｇｅ法建立包含摩擦项在内的泛函并在此基础上形成有限元列式并用Ｎ－Ｒ法迭代求解，通过对基体厚度耦合迭代和Ｒ－Ｔ模型来考虑空洞效应；文中分析了充模过程中变形的流动特点及材料参数、模具几何形状参数等对胀形过程和胀形件厚度分布的影响。

FINITE ELEMENT SIMULATION OF SUPERPLASTIC BULGING WITH SYMMETRIC DIE

In this paper,the process of superplastic bulging with symmetric die,which is chosen to be a conical one with arbitry slant angle(including cylinder),is investigated by large deformation rigid-viscoplastic finite element simulation,and the cavity effect is considered by the modification of the thickness of matrix and R-T medel. Eased on the functional including frictional one formed by Updated Lagrangian method,the FEM formulae are deduced and are solved by N-R iterative method.The effects of matetial parameters and geometric shape parameters etc.on the bulging process and the non-uniformity in the distribution of thickness of specimen are analysed.