Failure Prediction in Bulk Metal Forming Process

Abstract

An important concern in metal forming is whether the desired deformation can be accomplished without defects in the final product. Various ductile fracture criteria have been developed and experimentally verified for a limited number of cases of metal forming processes. These criteria are highly dependent on the geometry of the workpiece and cannot be utilized for complicated shapes without experimental verification. However, experimental work is a resource hungry process. This paper proposes the ability of finite element analysis (FEA) software such as LS-DYNA to pinpoint the crack-like flaws in bulk metal forming products. Two different approaches named as arbitrary Lagrangian-Eulerian (ALE) and smooth particle hydrodynamics (SPH) formulations were adopted. The results of the simulations agree well with the experimental work and a comparison between the two formulations has been carried out. Both approximation methods successfully predicted the flow of workpiece material (plastic deformation). However ALE method was able to pinpoint the location of the flaws.

A Useful Manufacturing Guide for Rotary Piercing Seamless Pipe by ALE Method

“…In this formulation, mesh movements and material movements are uncoupled, thus, reducing the elements' distortion. This formulation was proven to be successful in modelling the fluid-like behaviours of materials during bulk metal forming [31][32][33][34][35].…”

“…In this formulation, mesh movements and material movements are uncoupled, thus, reducing the elements' distortion. This formulation was proven to be successful in modelling the fluid-like behaviours of materials during bulk metal forming [31][32][33][34][35]. Vavourakis et al [36] used a decoupled ALE approach for the extensive deformation modelling of plane-strain elastoplastic problems and the obtained results were validated with limit analysis solutions.…”

A Useful Manufacturing Guide for Rotary Piercing Seamless Pipe by ALE Method

“…In this formulation, mesh movements and material movements are uncoupled, thus reducing the elements distortion. This formulation was proven to be successful in modelling the fluid-like behaviours of materials during bulk metal forming [31][32][33][34][35]. Vavourakis et al [36] used a decoupled ALE approach for the large deformation modelling of plane-strain elastoplastic problems and the obtained results were validated with limit analysis solutions.…”

3D Numerical Simulation of Seamless Pipe Piercing Process by Fluid-Structure Interaction Method

“…Therefore, a new formulation called Arbitrary Lagrangian-Eulerian (ALE) was introduced to solve these challenges. This method was proven to be successful in modelling the Fluid-Structure Interaction problems [7,8]. [9] In this paper, the numerical simulations of rotary piercing process are performed with Fluid-Structure Interaction analysis.…”