Effects of coating, holding force, stretching height, yield stress, and surface roughness on springback of steel in the V-stretch bending test

Abstract

Abstract Various types of defects can impact the mechanical or aesthetic properties of stamped sheets, and the phenomenon of springback (SB) is one of them. SB is complicated, and it is hard to simulate it precisely because it is related to many factors such as tooling geometry, material properties, friction, and boundary conditions. In this article, the SB of V-stretch bended samples with uncoated and coated steel is experimentally and numerically investigated. The steel samples are coated with a thin layer of several metals (zinc, tin, nickel, and chromium). This investigation takes into account the influence of various parameters such as the coating thickness, its roughness, the punch depth, the blank holding force (BHF), and the change in the material’s yield strength. A self-developed two-dimensional elastoplastic finite element code was developed using Abaqus/standard. In this work, we also show that the SB angle is smaller for uncoated sheet, higher BHF, higher surface roughness, lower coating thickness, lower stretching height, and lower yield strength.