A FE based machining simulation methodology accounting for cast iron microstructure

In the present paper the effect of graphite nodularity in the microstructure of cast iron is assessed with respect to its machinability at orthogonal cutting. A micro-structure based model of the cast iron material has been developed based on analyses of micro-graph images. The image analysis combines pearlitic grains with graphite nodules to produce the micro-structures. Continuous deformation behavior of pearlite and graphite phases is described using the Johnson-Cook (JC) viscoplasticty model including temperature dependence. Of particular concern is the modeling of the chip formation, induced by the micro-structure morphology and the mechanical behavior of the work piece material in the vicinity of the insert. This is described by the element deletion methodology along with the Johnson-Cook failure criterion to realize the fracture kinematics. A parametric study is carried out by varying the nodularity of the graphite. To validate the model, the finite element results are compared to machining test results carried out on a Compacted Graphite Iron (CGI) material in a related paper. It turns out that the FE-simulated and experimentally observed cutting force and chip formation compare fairly well.

[1]  David K. Aspinwall,et al.  Developments in modelling of metal cutting processes , 2007 .

[2]  S. Engin Kilic,et al.  A comparison of orthogonal cutting data from experiments with three different finite element models , 2004 .

[3]  Yuebin Guo,et al.  Dynamic Material Behavior Modeling Using Internal State Variable Plasticity and Its Application in Hard Machining Simulations , 2006 .

[4]  Abdur Razzaque,et al.  Automatic reduction of frontwidth for finite element analysis , 1980 .

[5]  D. Agard,et al.  Microtubule nucleation by γ-tubulin complexes , 2011, Nature Reviews Molecular Cell Biology.

[6]  M. G. Stevenson,et al.  Using the Finite Element Method to Determine Temperature Distributions in Orthogonal Machining , 1974 .

[7]  Fpt Frank Baaijens,et al.  An approach to micro-macro modeling of heterogeneous materials , 2001 .

[8]  T. Hughes,et al.  Finite rotation effects in numerical integration of rate constitutive equations arising in large‐deformation analysis , 1980 .

[9]  A. Sinatora,et al.  Numerical analysis of the stresses developed during the sliding of a cylinder over compact graphite iron , 2005 .

[10]  G. R. Johnson,et al.  Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures , 1985 .

[11]  A. Atkins.  Modelling metal cutting using modern ductile fracture mechanics: quantitative explanations for some longstanding problems , 2003 .

[12]  Stephen A. Langer,et al.  OOF: an image-based finite-element analysis of material microstructures , 2001, Comput. Sci. Eng..

[13]  T. Wierzbicki,et al.  Evaluation of six fracture models in high velocity perforation , 2006 .

[14]  Richard E. DeVor,et al.  Microstructure-Level Modeling of Ductile Iron Machining , 2001, Manufacturing Engineering.

[15]  Richard E. DeVor,et al.  Machining Simulation of Ductile Iron and Its Constituents, Part 1: Estimation of Material Model Parameters and Their Validation , 2001 .

[16]  Fabrizio Micari,et al.  A critical analysis on the friction modelling in orthogonal machining , 2007 .

[17]  Abdelwaheb Dogui,et al.  Development of a friction model for the tool-chip-workpiece interfaces during dry machining of AISI4142 steel with TiN coated carbide cutting tools , 2007 .

[18]  V. Astakhov.  On the inadequacy of the single-shear plane model of chip formation , 2005 .