Local and nonlocal strain gradient approaches for size-dependent plastic deformation

Local and nonlocal strain gradient approaches for size-dependent plastic deformation

ÜNSAL İzzet Erkin, GÜNAY Enes, YALÇINKAYA Tuncay

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Abstract. Micro scale manufacturing technologies have been a productive area of research due to the increase in miniaturization in various industries. However, most of the know-how in conventional metal forming processes cannot be readily transferred into micro/meso forming processes due to the size effect. By incorporating the length scale into the formulation, strain gradient theories offer a viable solution to the issues arising from size-dependent complications. This paper aims at implementing a lower-order strain gradient plasticity (SGP) theory developed from the Taylor dislocation model to numerically analyze the impact of the plastic size effect on the forming of metallic materials. The material model together with local and nonlocal approaches for the strain gradient calculations is implemented in a commercial finite element (FE) code through user subroutines. The flat punch indentation problem is examined using the implemented code.

Strain Gradient Plasticity, CMSG Theory, Size Effect, Finite Element Method

Published online 4/19/2023, 10 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: ÜNSAL İzzet Erkin, GÜNAY Enes, YALÇINKAYA Tuncay, Local and nonlocal strain gradient approaches for size-dependent plastic deformation, Materials Research Proceedings, Vol. 28, pp 1453-1462, 2023

DOI: https://doi.org/10.21741/9781644902479-157

The article was published as article 157 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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