A new three-dimensional finite element model for the simulation of powder forging processes: application to hot forming of P/M connecting rod

Abstract : In powder metallurgy (P/M) the forming of industrial artifacts requires consolidation of loose powder into dense material leading to near-to-net shape components. In order to realize the economic advantages of the near-to-net shape formation, it is essential to understand the mechanical behaviour of powder deforming domain. The conventional P/M forming process consists of different stages such as closed cold die compaction, sintering and hot/cold forging. In the present study a finite element based computational model has been formulated to study the hot forging stage with particular reference to forging of P/M connecting rods. In order to achieve this purpose, a new finite element formulation has been developed to model the powder deformation under a given thermo-mechanical loading. Essentially, the computational model is formulated based on a visco-plastic Green type material model considering an independent idealization of strain rates into a total deformation part and a dilatational part, and the yield criterion takes into account the pressure sensitivity. The model is set in a perturbed Lagrangian functional, leading to a three field mixed formulation with velocity, Lagrangian multiplier/pressure and volumetric strain rates as three basic unknowns in the finite element domain. The developed finite element model can be used right from the compressible domain to the incompressible domain with the Lagrangian multiplier becoming then the pressure. A relative density-dependent visco-plastic type of friction law is used for characterizing the friction behaviour between the powder preform and the die. The required various material parameters are determined from experiments on aluminium powder preforms. In order to facilitate the non-isothermal deformation study, a powder-based transient thermal analysis has been developed. A computational scheme has been used to couple the mechanical and thermal calculations. Using the developed three-dimensional code, hot forging of automotive components can be simulated and which in the present study is exemplified by simulation of hot forging of a P/M connecting rod.
Type de document :
Article dans une revue
Liste complète des métadonnées

https://hal-mines-paristech.archives-ouvertes.fr/hal-01420883
Contributeur : Magalie Prudon <>
Soumis le : mercredi 21 décembre 2016 - 10:58:41
Dernière modification le : lundi 12 novembre 2018 - 11:05:09

Lien texte intégral

Identifiants

Citation

Ashoka G.K. Jinka, Michel Bellet, Lionel Fourment. A new three-dimensional finite element model for the simulation of powder forging processes: application to hot forming of P/M connecting rod. International Journal for Numerical Methods in Engineering, Wiley, 1997, 40 (21), pp.3955 - 3978. ⟨10.1002/(SICI)1097-0207(19971115)40:21<3955::AID-NME210>3.0.CO;2-U⟩. ⟨hal-01420883⟩

Partager

Métriques

Consultations de la notice

264