Impact of compositional gradients on selectivity of dissolvable support structures for directed energy deposited metals

Christopher S. Lefky, Brian Zucker, Abdalla Ramadan Nassar, Timothy William Simpson, Owen J. Hildreth

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Functionally gradient materials (FGM) have many important applications due to their ability to possess vastly different material properties across the gradient. Recent work on dissolvable supports in stainless steel components fabricated using directed energy deposition (DED) show the utility of exploiting differences in the corrosion suseptibility in FGM metals. In order to better control the feature resolution of DED dissolvable supports, it is first necessary to understand how dilution and mixing within the gradient impact the local corrosion susceptibility and etch rates. In this work, FGMs with varying numbers of tracks and layers were fabricated onto a 304 stainless steel build plate; first one to three layers of 91 carbon steel followed by one to ten layers of 431 stainless steel. Metallography, potentiodynamic polarization plots, energy dispersive x-ray spectroscopy, and 3D contact profilometry data were collected to show that mixing within the gradient is very inhomogeneous. Incomplete mixing is observed throughout individual tracks along with widely varying composition and material properties from track-to-track, even within a single track. This paper demonstrates that the impact of incomplete mixing and composition gradients within a layer must be considered for DED-fabricated FGM dissolvable supports.

Original languageEnglish (US)
Pages (from-to)1-7
Number of pages7
JournalActa Materialia
Volume153
DOIs
StatePublished - Jul 1 2018

Fingerprint

Stainless Steel
Metals
Stainless steel
Materials properties
Corrosion
Profilometry
Functionally graded materials
Metallography
Potentiodynamic polarization
Chemical analysis
Dilution
Carbon steel
Spectroscopy
X rays

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Polymers and Plastics
  • Metals and Alloys

Cite this

@article{af435f52a7ed4a10b2fbf076793cfa26,
title = "Impact of compositional gradients on selectivity of dissolvable support structures for directed energy deposited metals",
abstract = "Functionally gradient materials (FGM) have many important applications due to their ability to possess vastly different material properties across the gradient. Recent work on dissolvable supports in stainless steel components fabricated using directed energy deposition (DED) show the utility of exploiting differences in the corrosion suseptibility in FGM metals. In order to better control the feature resolution of DED dissolvable supports, it is first necessary to understand how dilution and mixing within the gradient impact the local corrosion susceptibility and etch rates. In this work, FGMs with varying numbers of tracks and layers were fabricated onto a 304 stainless steel build plate; first one to three layers of 91 carbon steel followed by one to ten layers of 431 stainless steel. Metallography, potentiodynamic polarization plots, energy dispersive x-ray spectroscopy, and 3D contact profilometry data were collected to show that mixing within the gradient is very inhomogeneous. Incomplete mixing is observed throughout individual tracks along with widely varying composition and material properties from track-to-track, even within a single track. This paper demonstrates that the impact of incomplete mixing and composition gradients within a layer must be considered for DED-fabricated FGM dissolvable supports.",
author = "Lefky, {Christopher S.} and Brian Zucker and Nassar, {Abdalla Ramadan} and Simpson, {Timothy William} and Hildreth, {Owen J.}",
year = "2018",
month = "7",
day = "1",
doi = "10.1016/j.actamat.2018.04.009",
language = "English (US)",
volume = "153",
pages = "1--7",
journal = "Acta Materialia",
issn = "1359-6454",
publisher = "Elsevier Limited",

}

Impact of compositional gradients on selectivity of dissolvable support structures for directed energy deposited metals. / Lefky, Christopher S.; Zucker, Brian; Nassar, Abdalla Ramadan; Simpson, Timothy William; Hildreth, Owen J.

In: Acta Materialia, Vol. 153, 01.07.2018, p. 1-7.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Impact of compositional gradients on selectivity of dissolvable support structures for directed energy deposited metals

AU - Lefky, Christopher S.

AU - Zucker, Brian

AU - Nassar, Abdalla Ramadan

AU - Simpson, Timothy William

AU - Hildreth, Owen J.

PY - 2018/7/1

Y1 - 2018/7/1

N2 - Functionally gradient materials (FGM) have many important applications due to their ability to possess vastly different material properties across the gradient. Recent work on dissolvable supports in stainless steel components fabricated using directed energy deposition (DED) show the utility of exploiting differences in the corrosion suseptibility in FGM metals. In order to better control the feature resolution of DED dissolvable supports, it is first necessary to understand how dilution and mixing within the gradient impact the local corrosion susceptibility and etch rates. In this work, FGMs with varying numbers of tracks and layers were fabricated onto a 304 stainless steel build plate; first one to three layers of 91 carbon steel followed by one to ten layers of 431 stainless steel. Metallography, potentiodynamic polarization plots, energy dispersive x-ray spectroscopy, and 3D contact profilometry data were collected to show that mixing within the gradient is very inhomogeneous. Incomplete mixing is observed throughout individual tracks along with widely varying composition and material properties from track-to-track, even within a single track. This paper demonstrates that the impact of incomplete mixing and composition gradients within a layer must be considered for DED-fabricated FGM dissolvable supports.

AB - Functionally gradient materials (FGM) have many important applications due to their ability to possess vastly different material properties across the gradient. Recent work on dissolvable supports in stainless steel components fabricated using directed energy deposition (DED) show the utility of exploiting differences in the corrosion suseptibility in FGM metals. In order to better control the feature resolution of DED dissolvable supports, it is first necessary to understand how dilution and mixing within the gradient impact the local corrosion susceptibility and etch rates. In this work, FGMs with varying numbers of tracks and layers were fabricated onto a 304 stainless steel build plate; first one to three layers of 91 carbon steel followed by one to ten layers of 431 stainless steel. Metallography, potentiodynamic polarization plots, energy dispersive x-ray spectroscopy, and 3D contact profilometry data were collected to show that mixing within the gradient is very inhomogeneous. Incomplete mixing is observed throughout individual tracks along with widely varying composition and material properties from track-to-track, even within a single track. This paper demonstrates that the impact of incomplete mixing and composition gradients within a layer must be considered for DED-fabricated FGM dissolvable supports.

UR - http://www.scopus.com/inward/record.url?scp=85046149859&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85046149859&partnerID=8YFLogxK

U2 - 10.1016/j.actamat.2018.04.009

DO - 10.1016/j.actamat.2018.04.009

M3 - Article

VL - 153

SP - 1

EP - 7

JO - Acta Materialia

JF - Acta Materialia

SN - 1359-6454

ER -