Evaluation of Ductile Fracture Models in Finite Element Simulation of Metal Cutting Processes

Abstract

In this paper, a systematic evaluation of six ductile fi-acture models is conducted to identify the most suitable fracture criterion for metal cutting processes. Six fracture models are evaluated in this study, including constant fracture strain, Johnson-Cook, JohnsonCook coupling criterion, Wilkins, modified Cockcroft-Latham, and Bao-Wierzbicki fracture criterion. By means of ABAQUS built-in commands and a user material subroutine (VUMAT), these fracture models are implemented into a finite element (EE) model of orthogonal cutting processes in ABAQUSIExplicit platform. The local parameters (stress, strain, fracture factor, and velocity fields) and global variables (chip morphology, cutting forces, temperature, shear angle, and machined surface integrity) are evaluated. The numerical simulation results are examined by comparing to experimental results of2024-T3 aluminum alloy published in the open literature. Based on the results, it is found that damage evolution should be considered in cutting process EE simulation. Moreover, the B-W fracture model with consideration of rate dependency, temperature effect and damage evolution gives the best prediction of chip removal behavior of ductile metals.

3D Finite Element Modelling of Cutting Forces in Drilling Fibre Metal Laminates and Experimental Hole Quality Analysis

“…Previous numerical studies considered FE based and analytical-modelling of GLAREs to study their damage under high and low-speed impact, and blast loading primarily [7][8][9][10]. Development of FE models of machining metals and advanced alloys has surged over the years [11][12][13][14][15], while such application to GLAREs is not widely reported. The present work investigates the performance of aerospace structural material GLARE, a fibre metal laminate to machining process using twist drilling operations.…”

Surface Roughness Investigation and Stress Modeling by Finite Element on Orthogonal Cutting of Copper

“…When ( exceeds unity, the elements are supposed to fail and then discarded [35]. The tensile test data in typical stress-strain curve with progressive damage degradation are shown in Figure 3.…”

“…When the stress-strain curve approaches to point (d) the damage parameter (D) equals to unity. At that point, the stiffness of the material is completely degraded and the crack initiates as an indication of failure [35][36][37][38][39]. that point, the stiffness of the material is completely degraded and the crack initiates as an indication of failure [35][36][37][38][39].…”

“…In the case of plane stress, σ3 is zero and the equation can be defined in terms of two principle stresses as follows [35]:…”

Experimental and numerical analysis of the aluminum alloy AW5005 behavior subjected to tension and perforation under dynamic loading

“…In order to effectively apply the Johnson-Cook fracture model, researchers extended the model in different ways. Liu et al (2014) proved that the Johnson-Cook fracture model can be used as damage initiation coupled with damage evolution in metal cutting simulations. Moreover, the damage evolution combines two different fracture modes effects.…”