Thermo-micro-mechanical simulation of bulk metal forming processes

TL;DR

This paper presents a coupled thermo-micro-mechanical finite element simulation framework for bulk metal forming, integrating a microstructural constitutive model to accurately predict microstructural evolution during cold and warm forging processes.

Contribution

It introduces a microstructural solver integrated into FE software for coupled TMM simulation, enabling detailed analysis of microstructural evolution in metal forming.

Findings

Successful implementation of the microstructural solver in FE software.

Validation through simulation of industrial warm forging process.

Enhanced understanding of microstructural changes during forming.

Abstract

The newly proposed microstructural constitutive model for polycrystal viscoplasticity in cold and warm regimes (Motaman and Prahl, 2019), is implemented as a microstructural solver via user-defined material subroutine in a finite element (FE) software. Addition of the microstructural solver to the default thermal and mechanical solvers of a standard FE package enabled coupled thermo-micro-mechanical or thermal-microstructural-mechanical (TMM) simulation of cold and warm bulk metal forming processes. The microstructural solver, which incrementally calculates the evolution of microstructural state variables (MSVs) and their correlation to the thermal and mechanical variables, is implemented based on the constitutive theory of isotropic hypoelasto-viscoplastic (HEVP) finite (large) strain/deformation. The numerical integration and algorithmic procedure of the FE implementation are explained in detail. Then, the viability of this approach is shown for (TMM-) FE simulation of an industrial multistep warm forging.