Modeling single crystals: time integration, tangent operators, sensitivityanalysis and shape optimization

In this paper, a comprehensive overview of the numerical analysis of single crystalline materials at high temperatures is presented. including implici t higher order time integration, consistent linearization and respective: s ensitivity analysis. Both a phenomenological and a crystallographic model a re employed to simulate the mechanical isothermal behavior of the nickel-ba sed superalloy CMSX-4 at 950 degreesC in a finite element environment. A sh ape optimization methodology for resting specimen design based on extensive finite element computation is presented. The sensitivity analysis accordin g to the chosen time integration scheme is performed leading to an algorith m for simultaneous analysis and design (SAND). Examples for the shape optim ization of a cruciform specimen for biaxial tensile experiments at high tem peratures are given and discussed in detail. (C) 2001 Elsevier Science Ltd. All tights reserved.