Experimental characterisation of a CuAg alloy for thermo-mechanical applications. Part 1: Identifying parameters of non-linear plasticity models

Despite the wide use of copper alloys in thermo-mechanical applications, there is little data on their cyclic plasticity behaviour, particularly for CuAg alloys. This prevents the behaviour of the materials from being correctly described in numerical simulations for design purposes. In this work CuAg0.1 alloy used for thermo-mechanical applications was tested by strain-controlled cyclic loading at 3 different temperatures (room temperature, 250°C, 300°C). In each test, stress-strain cycles were recorded until the alloy had completely stabilised. These cycles were then used to identify material parameters of non-linear kinematic and isotropic models. The focus was on plasticity models (Armstrong-Frederick, Chaboche, Voce) that are usually implemented in commercial finite element codes. Simulated cyclic responses with the identified material models were compared with experiments and showed a good agreement. The identified material parameters for the CuAg alloy under investigation can be used directly in finite element models for cyclic plasticity simulations, thus enabling a durability analysis of components under thermo-mechanical loads to be performed, particularly in the field of steel-making plants.