Modeling of the size effects on the behavior of metals in microscale deformation processes

Gap Yong Kim, Jun Ni, Muammer Koç

Research output: Contribution to journalArticle

107 Citations (Scopus)


For the accurate analysis and design of microforming process, proper modeling of material behavior at the micro/mesoscale is necessary by considering the size effects. Two size effects are known to exist in metallic materials. One is the "grain size" effect, and the other is the "feature/specimen size" effect. This study investigated the feature/specimen size effect and introduced a scaling model which combined both feature/specimen and grain size effects. Predicted size effects were compared with three separate experiments obtained from previous research: a simple compression with a round specimen, a simple tension with a round specimen, and a simple tension in sheet metal. The predicted results had a very good agreement with the experiments. Quantification of the miniaturization effect has been achieved by introducing two parameters, α and β, which can be determined by the scaling parameter n, to the Hall-Petch equation. The scaling model offers a simple way to model the size effect down to length scales of a couple of grains and to extend the use of continuum plasticity theories to micro/mesolength scales.

Original languageEnglish
Pages (from-to)470-476
Number of pages7
JournalJournal of Manufacturing Science and Engineering, Transactions of the ASME
Issue number3
Publication statusPublished - Jun 2007
Externally publishedYes



  • Microforming
  • Miniaturization
  • Scaling effect
  • Size effect

ASJC Scopus subject areas

  • Industrial and Manufacturing Engineering
  • Mechanical Engineering

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