Multi-Resolution Material Hardening Law for CPFE Micro-Forming Analysis

Abstract:

A new multi-resolution slip system-based material hardening law has been developed for micro-forming simulation using Crystal Plasticity Finite Element (CPFE) Approach. Material hardenings are formulated based on global and local hardening of dislocations for each slip system and defined with distinct physical meaning. Plasticity is assumed to arise solely from crystalline slip and the overall mechanical response with any crystallographic system, such as FCC, BCC, etc, can be addressed by a local hardening parameter, c, from 0 (pure anisotropic) to 1 (fully isotropic). No interaction matrix is necessary, since the latent hardening can be realized by the hardening factor , c , and the new dislocation density based hardening law can be implemented into existing FE software efficiently. The proposed equations are an extension of the existing hardening law from macro mechanics descriptions down to micro mechanics level, therefore unified constitutive equations had been established at multiscale resolution. Some features of the proposed hardening law will be demonstrated with a single cubic crystal under tension load.

• Periodical: Key Engineering Materials (Volume 716)
• Pages: 232-239
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.716.232
• Online since: October 2016
• Authors: Ji Ling Feng*, Shi Wen Wang, Jian Guo Lin
• Keywords: Crystal Plasticity Finite Element (CPFE), Hardening Law

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