Transverse bending of a rectangular workpiece at large plastic deformations

Abstract

The technological operation of bending is widely used in the manufacture of various parts — both rod parts, for example, springs of various types, and shell parts, for example, shells and bottoms of petrochemical apparatuses, ship hulls, automobiles, etc. The maximum plastic strains that arise in this case vary over a wide range and can reach quite large values, significantly exceeding the elastic strains. Regardless of the maximum deformation levels, residual stresses occur in the product, affecting its performance. The study of free three-point bending of a workpiece with a rectangular cross section was carried out at different ratios of the radius of the punch contacting cylindrical surface to the height of the workpiece as well as at different ratios of the width to the height of the workpiece. The workpiece material is low-carbon steel with a real (not approximated) deformation diagram. Stress state, cross-sectional shape change and residual stresses are numerically investigated using the finite element method.