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High-resolution Digital Image Correlation (HR-DIC) was performed on an Inconel 718 specimen, which was subjected to a heat treatment to form a fully solutionized system. In-situ measurements in the small strain regime were made through SEM imaging, followed by HR-DIC to extract quantitative representations of the strain and in-plane displacement induced by deformation events during plastic deformation.
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Deformation Behavior of Grains Near Defects in Direct Metal Laser Sintered Inconel 718 During Indentation
Abstract The present work utilizes Orientation Imaging Microscopy and Finite Element Modelling to analyse microstructure evolution in grains near defects during plane strain indentation of direct metal laser sintered Inconel 718. Defects are inevitably produced during printing of metals and they degrade the mechanical behaviour of parent components. Understanding microstructure evolution of grains present near defects can help create better predictive models of mechanical behaviour of components resulting from additive manufacturing. In this work, an ex-situ study of microstructure evolution during plane strain indentation of DMLS Inconel 718 specimens is performed. Regions that lie near volumetric porosity defects were studied. Grain Orientation Spread was utilized as a metric to quantify intra-granular deformation. It was seen that microstructure evolution of grains near defects is enhanced due to strain concentrations whereby they exhibit larger orientation spread after plastic deformation. Finite Element Analysis was used to simulate the plane strain indentation test on the specimen in which, porosity defects and roughness textures similar to those seen in the as-received specimen were programmed using the python scripting interface of Abaqus. Results from finite element analysis were compared with insights from microstructure analysis to describe evolution of microstructure during deformation near defects.
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- Award ID(s):
- 1825686
- PAR ID:
- 10483142
- Publisher / Repository:
- American Society of Mechanical Engineers
- Date Published:
- Journal Name:
- Proceedings of the ASME 2020 15th International Manufacturing Science and Engineering Conference MSEC2020
- ISBN:
- 978-0-7918-8425-6
- Format(s):
- Medium: X
- Location:
- Virtual, Online
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1115/MSEC2020-8442
