Pore elimination mechanisms during 3D printing of metals

Hojjatzadeh, S. Mohammad H.; Parab, Niranjan D.; Yan, Wentao; Guo, Qilin; Xiong, Lianghua; Zhao, Cang; Qu, Minglei; Escano, Luis I.; Xiao, Xianghui; Fezzaa, Kamel; Everhart, Wes; Sun, Tao; Chen, Lianyi

doi:10.1038/s41467-019-10973-9

Title: Pore elimination mechanisms during 3D printing of metals

Abstract

Laser powder bed fusion (LPBF) is a 3D printing technology that can print metal parts with complex geometries without the design constraints of traditional manufacturing routes. However, the parts printed by LPBF normally contain many more pores than those made by conventional methods, which severely deteriorates their properties. Here, by combining in-situ high-speed high-resolution synchrotron x-ray imaging experiments and multi-physics modeling, we unveil the dynamics and mechanisms of pore motion and elimination in the LPBF process. We find that the high thermocapillary force, induced by the high temperature gradient in the laser interaction region, can rapidly eliminate pores from the melt pool during the LPBF process. The thermocapillary force driven pore elimination mechanism revealed here may guide the development of 3D printing approaches to achieve pore-free 3D printing of metals.

Authors:

^[1];

^[2];

^[3];

^[1];

^[2];

^[1]; Escano, Luis I. ^[1];

^[2];

^[4];

^[2];

^[1]

Missouri Univ. of Science and Technology, Rolla, MO (United States)
Argonne National Lab. (ANL), Lemont, IL (United States)
National Univ. of Singapore (Singapore)
Honeywell FM&T, Kansas City, MO (United States)

Publication Date:: 2019-07-12

Research Org.:: Argonne National Lab. (ANL), Argonne, IL (United States)

Sponsoring Org.:: USDOE Office of Enterprise Assessments, Kansas City National Security Campus; National Science Foundation (NSF); Argonne National Laboratory, Laboratory Directed Research and Development (LDRD); USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:: 1572905

Grant/Contract Number:: AC02-06CH11357

Resource Type:: Accepted Manuscript

Journal Name:: Nature Communications

Additional Journal Information:: Journal Volume: 10; Journal Issue: 1; Journal ID: ISSN 2041-1723

Publisher:: Nature Publishing Group

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

Citation Formats


                    Hojjatzadeh, S. Mohammad H., Parab, Niranjan D., Yan, Wentao, Guo, Qilin, Xiong, Lianghua, Zhao, Cang, Qu, Minglei, Escano, Luis I., Xiao, Xianghui, Fezzaa, Kamel, Everhart, Wes, Sun, Tao, and Chen, Lianyi. Pore elimination mechanisms during 3D printing of metals.  United States: N. p., 2019. 
Web.  doi:10.1038/s41467-019-10973-9.

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                    Hojjatzadeh, S. Mohammad H., Parab, Niranjan D., Yan, Wentao, Guo, Qilin, Xiong, Lianghua, Zhao, Cang, Qu, Minglei, Escano, Luis I., Xiao, Xianghui, Fezzaa, Kamel, Everhart, Wes, Sun, Tao, & Chen, Lianyi. Pore elimination mechanisms during 3D printing of metals.  United States.  https://doi.org/10.1038/s41467-019-10973-9

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                    Hojjatzadeh, S. Mohammad H., Parab, Niranjan D., Yan, Wentao, Guo, Qilin, Xiong, Lianghua, Zhao, Cang, Qu, Minglei, Escano, Luis I., Xiao, Xianghui, Fezzaa, Kamel, Everhart, Wes, Sun, Tao, and Chen, Lianyi. Fri .  
"Pore elimination mechanisms during 3D printing of metals".  United States.  https://doi.org/10.1038/s41467-019-10973-9.  https://www.osti.gov/servlets/purl/1572905.

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@article{osti_1572905,

  title        = {Pore elimination mechanisms during 3D printing of metals},

  author       = {Hojjatzadeh, S. Mohammad H. and Parab, Niranjan D. and Yan, Wentao and Guo, Qilin and Xiong, Lianghua and Zhao, Cang and Qu, Minglei and Escano, Luis I. and Xiao, Xianghui and Fezzaa, Kamel and Everhart, Wes and Sun, Tao and Chen, Lianyi},

  abstractNote = {Laser powder bed fusion (LPBF) is a 3D printing technology that can print metal parts with complex geometries without the design constraints of traditional manufacturing routes. However, the parts printed by LPBF normally contain many more pores than those made by conventional methods, which severely deteriorates their properties. Here, by combining in-situ high-speed high-resolution synchrotron x-ray imaging experiments and multi-physics modeling, we unveil the dynamics and mechanisms of pore motion and elimination in the LPBF process. We find that the high thermocapillary force, induced by the high temperature gradient in the laser interaction region, can rapidly eliminate pores from the melt pool during the LPBF process. The thermocapillary force driven pore elimination mechanism revealed here may guide the development of 3D printing approaches to achieve pore-free 3D printing of metals.},

  doi          = {10.1038/s41467-019-10973-9},

  journal      = {Nature Communications},

  number       = 1,

  volume       = 10,

  place        = {United States},

  year         = {2019},

  month        = {7}

}

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Works referencing / citing this record:

The origin of high-density dislocations in additively manufactured metals
journal, April 2020

Wang, Ge; Ouyang, Heng; Fan, Chen
Materials Research Letters, Vol. 8, Issue 8
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The origin of high-density dislocations in additively manufactured metals
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Wang, Ge; Ouyang, Heng; Fan, Chen
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Title: Pore elimination mechanisms during 3D printing of metals

Abstract

Citation Formats

Dynamics of keyhole and molten pool in laser welding journal, December 1998

TomoPy: a framework for the analysis of synchrotron tomographic data journal, August 2014

Analyzing the effects of powder and post-processing on porosity and properties of electron beam melted Ti-6Al-4V journal, June 2017

Data-driven multi-scale multi-physics models to derive process–structure–property relationships for additive manufacturing journal, January 2018

Multi-scale modeling of electron beam melting of functionally graded materials journal, August 2016

Production of Al-(12?25) wt% Si alloys by rapid solidification: melt spinning versus centrifugal atomization journal, January 1992

The dynamics of vapor bubbles in nonuniform temperature fields journal, March 1961

Additive manufacturing of metallic components – Process, structure and properties journal, March 2018

Dynamic simulation of dispersed gas-liquid two-phase flow using a discrete bubble model journal, May 1997

In situ X-ray imaging of defect and molten pool dynamics in laser additive manufacturing journal, April 2018

Oxides, porosity and fatigue performance of AlSi10Mg parts produced by selective laser melting journal, January 2017

An instrument for in situ time-resolved X-ray imaging and diffraction of laser powder bed fusion additive manufacturing processes journal, May 2018

Laser additive manufacturing of metallic components: materials, processes and mechanisms journal, May 2012

Surface tension of binary Al–Si liquid alloys journal, February 2015

Ultrafast X-ray imaging of laser–metal additive manufacturing processes journal, August 2018

Laser powder-bed fusion additive manufacturing: Physics of complex melt flow and formation mechanisms of pores, spatter, and denudation zones journal, April 2016

Formation and reduction of hydrogen porosity during selective laser melting of AlSi10Mg journal, July 2015

Improving surface finish in pulsed laser micro polishing using thermocapillary flow journal, January 2013

Bubble flow characteristics in bubble columns at elevated pressure and temperature journal, March 1998

The motion of bubbles in a vertical temperature gradient journal, October 1959

The hydrodynamics of bubble rise and impact with solid surfaces journal, September 2016

Laser cladding journal, April 1999

On the mechanism of porosity formation during welding of titanium alloys journal, April 2012

Rapid control of phase growth by nanoparticles journal, May 2014

The metallurgy and processing science of metal additive manufacturing journal, March 2016

Multi-physics modeling of single/multiple-track defect mechanisms in electron beam selective melting journal, August 2017

Porosity regrowth during heat treatment of hot isostatically pressed additively manufactured titanium components journal, September 2016

Real-time monitoring of laser powder bed fusion process using high-speed X-ray imaging and diffraction journal, June 2017

On the mechanical behaviour of titanium alloy TiAl6V4 manufactured by selective laser melting: Fatigue resistance and crack growth performance journal, March 2013

A Foil-Based Additive Manufacturing Technology for Metal Parts journal, August 2016

Transient dynamics of powder spattering in laser powder bed fusion additive manufacturing process revealed by in-situ high-speed high-energy x-ray imaging journal, June 2018

Formation of Immiscible Alloy Powders with Egg-Type Microstructure journal, August 2002

3D printing of high-strength aluminium alloys journal, September 2017

TomoPy: A framework for the analysis of synchrotron tomographic data conference, September 2014

Laser Cladding text, January 1983

The origin of high-density dislocations in additively manufactured metals journal, April 2020

The origin of high-density dislocations in additively manufactured metals text, January 2020

Dynamics of keyhole and molten pool in laser welding
journal, December 1998

TomoPy: a framework for the analysis of synchrotron tomographic data
journal, August 2014

Analyzing the effects of powder and post-processing on porosity and properties of electron beam melted Ti-6Al-4V
journal, June 2017

Data-driven multi-scale multi-physics models to derive process–structure–property relationships for additive manufacturing
journal, January 2018

Multi-scale modeling of electron beam melting of functionally graded materials
journal, August 2016

Production of Al-(12?25) wt% Si alloys by rapid solidification: melt spinning versus centrifugal atomization
journal, January 1992

The dynamics of vapor bubbles in nonuniform temperature fields
journal, March 1961

Additive manufacturing of metallic components – Process, structure and properties
journal, March 2018

Dynamic simulation of dispersed gas-liquid two-phase flow using a discrete bubble model
journal, May 1997

In situ X-ray imaging of defect and molten pool dynamics in laser additive manufacturing
journal, April 2018

Oxides, porosity and fatigue performance of AlSi10Mg parts produced by selective laser melting
journal, January 2017

An instrument for in situ time-resolved X-ray imaging and diffraction of laser powder bed fusion additive manufacturing processes
journal, May 2018

Laser additive manufacturing of metallic components: materials, processes and mechanisms
journal, May 2012

Surface tension of binary Al–Si liquid alloys
journal, February 2015

Ultrafast X-ray imaging of laser–metal additive manufacturing processes
journal, August 2018

Laser powder-bed fusion additive manufacturing: Physics of complex melt flow and formation mechanisms of pores, spatter, and denudation zones
journal, April 2016

Formation and reduction of hydrogen porosity during selective laser melting of AlSi10Mg
journal, July 2015

Improving surface finish in pulsed laser micro polishing using thermocapillary flow
journal, January 2013

Bubble flow characteristics in bubble columns at elevated pressure and temperature
journal, March 1998

The motion of bubbles in a vertical temperature gradient
journal, October 1959

The hydrodynamics of bubble rise and impact with solid surfaces
journal, September 2016

Laser cladding
journal, April 1999

On the mechanism of porosity formation during welding of titanium alloys
journal, April 2012

Rapid control of phase growth by nanoparticles
journal, May 2014

The metallurgy and processing science of metal additive manufacturing
journal, March 2016

Multi-physics modeling of single/multiple-track defect mechanisms in electron beam selective melting
journal, August 2017

Porosity regrowth during heat treatment of hot isostatically pressed additively manufactured titanium components
journal, September 2016

Real-time monitoring of laser powder bed fusion process using high-speed X-ray imaging and diffraction
journal, June 2017

On the mechanical behaviour of titanium alloy TiAl6V4 manufactured by selective laser melting: Fatigue resistance and crack growth performance
journal, March 2013

A Foil-Based Additive Manufacturing Technology for Metal Parts
journal, August 2016

Transient dynamics of powder spattering in laser powder bed fusion additive manufacturing process revealed by in-situ high-speed high-energy x-ray imaging
journal, June 2018

Formation of Immiscible Alloy Powders with Egg-Type Microstructure
journal, August 2002

3D printing of high-strength aluminium alloys
journal, September 2017

TomoPy: A framework for the analysis of synchrotron tomographic data
conference, September 2014

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text, January 1983

The origin of high-density dislocations in additively manufactured metals
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The origin of high-density dislocations in additively manufactured metals
text, January 2020