Evaluation of deformation inhomogeneity in multi-layered steel-titanium and steel-magnesium systems

In the presented study, plastometric tests using channel die compression were employed to define the boundary conditions for numerical simulations of the deformation processes of heterogeneous multi-layer systems composed of microalloyed steel, titanium, or magnesium. Various configurations, conditions, and deformation schemes were applied, which were then replicated in numerical simulations. Rheological models were used in the studies which, through computer simulations, enabled the modeling of interactions between the incoherent components of the microstructure. The primary outcome of the conducted experimental studies and numerical simulations is the ability to assess the heterogeneity of the studied multi-layer systems in terms of their mechanical states and influence on microstructural changes. This heterogeneity additionally arises from the diverse microstructural and rheological characteristics of the investigated materials (BCC vs. HCP), which, in turn, affect the strengthening mechanisms, primarily strain hardening. The results obtained from channel die compression tests were then used in simulations of multi-stage wire drawing, supporting both the design phase and the analysis of the resulting microstructural effects in the studied heterogeneous systems. It was observed that one of the key criteria for designing heterostructured wires from the examined materials is the proper selection of the volume fraction of the components, as well as the deformation history during multi-stage wire drawing, considering interpass heat treatment.