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Title: Effect of process parameters on hardness, temperature profile and solidification of different layers processed by direct metal laser sintering (DMLS)

Abstract

In DMLS process objects are fabricated layer by layer from powdered material by melting induced by a controlled laser beam. Metallic powder melts and solidifies to form a single layer. Solidification map during layer formation is an important route to characterize micro-structure and grain morphology of sintered layer. Generally, solidification leads to columnar, equiaxed or mixture of these two types grain morphology depending on solidification rate and thermal gradient. Eutectic or dendritic structure can be formed in fully equiaxed zone. This dendritic growth has a large effect on material properties. Smaller dendrites generally increase ductility of the layer. Thus, materials can be designed by creating desired grain morphology in certain regions using DMLS process. To accomplish this, hardness, temperature distribution, thermal gradient and solidification cooling rate in processed layers will be studied under change of process variables by using finite element analysis, with specific application to Ti-6Al-4V.

Authors:
; ;  [1]
  1. Department of Mechanical and Materials Engineering, Wright State University, Dayton, Ohio 45435 (United States)
Publication Date:
OSTI Identifier:
22608565
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1754; Journal Issue: 1; Conference: ICME 2015: 11. international conference on mechanical engineering, Dhaka (Bangladesh), 18-20 Dec 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BEAMS; COOLING; DENDRITES; DUCTILITY; FINITE ELEMENT METHOD; HARDNESS; LASER RADIATION; LAYERS; MELTING; MICROSTRUCTURE; MIXTURES; POWDERS; SINTERING; SOLIDIFICATION; TEMPERATURE DISTRIBUTION; TEMPERATURE GRADIENTS

Citation Formats

Ahmed, Sazzad Hossain, Mian, Ahsan, E-mail: ahsan.mian@wright.edu, and Srinivasan, Raghavan. Effect of process parameters on hardness, temperature profile and solidification of different layers processed by direct metal laser sintering (DMLS). United States: N. p., 2016. Web. doi:10.1063/1.4958437.
Ahmed, Sazzad Hossain, Mian, Ahsan, E-mail: ahsan.mian@wright.edu, & Srinivasan, Raghavan. Effect of process parameters on hardness, temperature profile and solidification of different layers processed by direct metal laser sintering (DMLS). United States. doi:10.1063/1.4958437.
Ahmed, Sazzad Hossain, Mian, Ahsan, E-mail: ahsan.mian@wright.edu, and Srinivasan, Raghavan. 2016. "Effect of process parameters on hardness, temperature profile and solidification of different layers processed by direct metal laser sintering (DMLS)". United States. doi:10.1063/1.4958437.
@article{osti_22608565,
title = {Effect of process parameters on hardness, temperature profile and solidification of different layers processed by direct metal laser sintering (DMLS)},
author = {Ahmed, Sazzad Hossain and Mian, Ahsan, E-mail: ahsan.mian@wright.edu and Srinivasan, Raghavan},
abstractNote = {In DMLS process objects are fabricated layer by layer from powdered material by melting induced by a controlled laser beam. Metallic powder melts and solidifies to form a single layer. Solidification map during layer formation is an important route to characterize micro-structure and grain morphology of sintered layer. Generally, solidification leads to columnar, equiaxed or mixture of these two types grain morphology depending on solidification rate and thermal gradient. Eutectic or dendritic structure can be formed in fully equiaxed zone. This dendritic growth has a large effect on material properties. Smaller dendrites generally increase ductility of the layer. Thus, materials can be designed by creating desired grain morphology in certain regions using DMLS process. To accomplish this, hardness, temperature distribution, thermal gradient and solidification cooling rate in processed layers will be studied under change of process variables by using finite element analysis, with specific application to Ti-6Al-4V.},
doi = {10.1063/1.4958437},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1754,
place = {United States},
year = 2016,
month = 7
}
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