Micro-indentation based study on steel sheet degradation through forming and flattening: Toward a predictive model to assess cold recyclability

Abstract

Article history:In Cold Roll Forming (CRF) process sheet material undergo a complex set of deformation that entail complicated through thickness residual deformation. This paper, focuses on material behaviour in CRF processes, with regarding damage and material degradation. A roll forming process is taken as case study and experimental investigation using extensive microhardness mapping alongside FE simulation of the process are the basis of material damage study. Indentation on different cross-sectional cutting angles -45, 0, 45 has been performed to study the sensitivity to orientation and crystallographic texture. A 3D Finite Element simulation with emphasis on through-thickness variation of the plastic deformation was carried out, using multiple layers of solid elements representing the sheet. A smart approach to reduce computational cost was employed in MSC.Marc by implementing simulation of a master model of complete material with shell elements, followed by partial submodelling comprising solid elements in regions of interest. This cross-sectional hardness map was then converted to the corresponding equivalent plastic strain in the cross section for validation. The correlation factor between Hardness and yield stress was discussed.

Computational assessment of residual formability in sheet metal forming processes for sustainable recycling

“…A comparison was made to verify the developed model and experimental results presented by Falsafi and Demirci (2016) for the formability assessments after unbending the fold zones of a cold roll formed profile. Their experiment was carried out on the same material used in this study, and based on the reported change in formability and the geometrical parameters in their profile, three points are extracted for verification ( see Table 3 ).…”