Effect of Hatch Spacing on Melt Pool and As-built Quality During Selective Laser Melting of Stainless Steel: Modeling and Experimental Approaches

In this study, a combined simulation and experimental approach is utilized to investigate the influence of hatch spacing on the microstructure and as-built quality of 316L stainless steel (SS) samples fabricated by selective laser melting (SLM). A three-dimensional finite element model (FEM) is empl...

Full description

Bibliographic Details
Main Authors: Zhichao Dong, Yabo Liu, Weibin Wen, Jingran Ge, Jun Liang
Format: Article
Language:English
Published: MDPI AG 2018-12-01
Series:Materials
Subjects:
Online Access:http://www.mdpi.com/1996-1944/12/1/50
id doaj-ca666d07e8634933841336d291a1f251
record_format Article
spelling doaj-ca666d07e8634933841336d291a1f2512020-11-25T01:18:29ZengMDPI AGMaterials1996-19442018-12-011215010.3390/ma12010050ma12010050Effect of Hatch Spacing on Melt Pool and As-built Quality During Selective Laser Melting of Stainless Steel: Modeling and Experimental ApproachesZhichao Dong0Yabo Liu1Weibin Wen2Jingran Ge3Jun Liang4Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, ChinaInstitute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, ChinaSchool of Civil Engineering, Central South University, Changsha, 410083, ChinaInstitute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, ChinaInstitute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, ChinaIn this study, a combined simulation and experimental approach is utilized to investigate the influence of hatch spacing on the microstructure and as-built quality of 316L stainless steel (SS) samples fabricated by selective laser melting (SLM). A three-dimensional finite element model (FEM) is employed to investigate heat transfer and melt pool during the SLM of 316L SS. The phase transformation and variation of the thermo-physical properties of the materials are considered in this model. The effects of hatch spacing (H) on the temperature field, microstructure and melt pool size, overlap rate, surface quality, and relative density during the SLM of 316L SS are investigated. The simulated results indicate that, as the hatch spacing increases, the depth increases and the width of the melt pool decreases. Meanwhile, with the increase of hatch spacing, the simulated temperature of the subsequent tracks falls below the melting temperature of the first track. Moreover, the microstructures were found to coarsen with the increasing hatch spacing due to the reduced cooling rate. The optimized hatch spacing and overlap rate between adjacent tracks were obtained from numerical simulations. Simulation results illustrate that, when the optimized hatch spacing of 100 μm is adopted, fully dense parts with a smooth surface can be fabricated by SLM, thus experimentally validating the simulation results.http://www.mdpi.com/1996-1944/12/1/50hatch spacingoverlap rateselective laser meltingstainless steel microstructurerelative density
collection DOAJ
language English
format Article
sources DOAJ
author Zhichao Dong
Yabo Liu
Weibin Wen
Jingran Ge
Jun Liang
spellingShingle Zhichao Dong
Yabo Liu
Weibin Wen
Jingran Ge
Jun Liang
Effect of Hatch Spacing on Melt Pool and As-built Quality During Selective Laser Melting of Stainless Steel: Modeling and Experimental Approaches
Materials
hatch spacing
overlap rate
selective laser melting
stainless steel microstructure
relative density
author_facet Zhichao Dong
Yabo Liu
Weibin Wen
Jingran Ge
Jun Liang
author_sort Zhichao Dong
title Effect of Hatch Spacing on Melt Pool and As-built Quality During Selective Laser Melting of Stainless Steel: Modeling and Experimental Approaches
title_short Effect of Hatch Spacing on Melt Pool and As-built Quality During Selective Laser Melting of Stainless Steel: Modeling and Experimental Approaches
title_full Effect of Hatch Spacing on Melt Pool and As-built Quality During Selective Laser Melting of Stainless Steel: Modeling and Experimental Approaches
title_fullStr Effect of Hatch Spacing on Melt Pool and As-built Quality During Selective Laser Melting of Stainless Steel: Modeling and Experimental Approaches
title_full_unstemmed Effect of Hatch Spacing on Melt Pool and As-built Quality During Selective Laser Melting of Stainless Steel: Modeling and Experimental Approaches
title_sort effect of hatch spacing on melt pool and as-built quality during selective laser melting of stainless steel: modeling and experimental approaches
publisher MDPI AG
series Materials
issn 1996-1944
publishDate 2018-12-01
description In this study, a combined simulation and experimental approach is utilized to investigate the influence of hatch spacing on the microstructure and as-built quality of 316L stainless steel (SS) samples fabricated by selective laser melting (SLM). A three-dimensional finite element model (FEM) is employed to investigate heat transfer and melt pool during the SLM of 316L SS. The phase transformation and variation of the thermo-physical properties of the materials are considered in this model. The effects of hatch spacing (H) on the temperature field, microstructure and melt pool size, overlap rate, surface quality, and relative density during the SLM of 316L SS are investigated. The simulated results indicate that, as the hatch spacing increases, the depth increases and the width of the melt pool decreases. Meanwhile, with the increase of hatch spacing, the simulated temperature of the subsequent tracks falls below the melting temperature of the first track. Moreover, the microstructures were found to coarsen with the increasing hatch spacing due to the reduced cooling rate. The optimized hatch spacing and overlap rate between adjacent tracks were obtained from numerical simulations. Simulation results illustrate that, when the optimized hatch spacing of 100 μm is adopted, fully dense parts with a smooth surface can be fabricated by SLM, thus experimentally validating the simulation results.
topic hatch spacing
overlap rate
selective laser melting
stainless steel microstructure
relative density
url http://www.mdpi.com/1996-1944/12/1/50
work_keys_str_mv AT zhichaodong effectofhatchspacingonmeltpoolandasbuiltqualityduringselectivelasermeltingofstainlesssteelmodelingandexperimentalapproaches
AT yaboliu effectofhatchspacingonmeltpoolandasbuiltqualityduringselectivelasermeltingofstainlesssteelmodelingandexperimentalapproaches
AT weibinwen effectofhatchspacingonmeltpoolandasbuiltqualityduringselectivelasermeltingofstainlesssteelmodelingandexperimentalapproaches
AT jingrange effectofhatchspacingonmeltpoolandasbuiltqualityduringselectivelasermeltingofstainlesssteelmodelingandexperimentalapproaches
AT junliang effectofhatchspacingonmeltpoolandasbuiltqualityduringselectivelasermeltingofstainlesssteelmodelingandexperimentalapproaches
_version_ 1725142287680274432