A model for damage coalescence in heterogeneous multi-phase materials

Justin Gammage, David Wilkinson, Yves Brechet, David Embury

Research output: Contribution to journalArticleResearchpeer-review

33 Citations (Scopus)

Abstract

Previous models for the deformation of two-phase materials with heterogeneous second phase distributions have been extended to account for damage coalescence. As in the previous work, the model is based on a self-consistent analysis and uses an incremental, tangent modulus approach. Damage coalescence is treated through a micro-crack linkage model that is sensitive to both the local volume fraction of damaged second phase particles and the local stress acting between damaged particles. This work suggests that micro-crack linkage rapidly leads to a loss of global stability and is critical in limiting the ductility exhibited by materials, at least for those exhibiting damage by particle cracking. Thus experimental data for metal-matrix composites agree well with the predictions of the micro-crack linkage model. Ductility predictions resulting from the model are sensitive to both the volume fraction and matrix work hardening exponent. By varying the latter over a range typical of aluminum alloys the model captures the experimentally observed range of ductility for a wide range of Al-based MMCs.

Original languageEnglish
Pages (from-to)5255-5263
Number of pages9
JournalActa Materialia
Volume52
Issue number18
DOIs
Publication statusPublished - 18 Oct 2004
Externally publishedYes

Keywords

  • Damage
  • Ductility
  • Fracture
  • Metal matrix composite
  • Self-consistent model

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