A robust simulation of Direct Drive Friction Welding with a modified Carreau fluid constitutive model

The subject of this paper is the presentation of a holistic, fully-temperature-coupled simulation of Direct Drive Friction Welding (DDFW) based on the modified Carreau fluid model. The main motivation therein is the consistent and stable prediction of suitable process parameters, which is still the major problem in adopting Rotary Friction Welding (RFW) processes to new pairs of weld partners at industrial applications. The Carreau type fluid constitutive equation is derived from a Norton-Bailey law wherein the temperature dependency is accounted for by a Johnson-Cook power approach. Its main benefit is the stable and robust simulation of the process and the physical palpability of the utilized material parameters. Using a special element formulation on the general axisymmetric frame in conjunction with an Augmented Lagrange bulk viscosity term, a purely displacement based form of the numerical solution procedure is applicable. A penalty contact approach together with a regularized friction law allow for an efficient determination of the interface pressure and friction forces. The model's performance is demonstrated by means of a test problem highlighting the potential of adopting it to industrial applications later on. (C) 2013 Elsevier B.V. All rights reserved.