TY - JOUR
T1 - Intra-layer closed-loop control of build plan during directed energy additive manufacturing of Ti-6Al-4V
AU - Nassar, Abdalla R.
AU - Keist, Jayme S.
AU - Reutzel, Edward W.
AU - Spurgeon, Todd J.
N1 - Funding Information:
We acknowledge Mr. Edward A. Good for assistance in preparing metallographic samples. Funding for this work was provided by the Office of Naval Research , under Contract No. N00014-11-1-0668. Any opinions, findings and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the Office of Naval Research.
Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2015/4/1
Y1 - 2015/4/1
N2 - The location, timing, and arrangement of depositions paths used to build an additively manufactured component - collectively called the build plan - are known to impact local thermal history, microstructure, thermal distortion, and mechanical properties. In this work, a novel system architecture for intra-layer, closed-loop control of the build plan is introduced and demonstrated for directed-energy deposition of Ti-6Al-4V. The control strategy altered the build plan in real time to ensure that the temperature around the start point of each hatch, prior to deposition, was below a threshold temperature of 415. °C. Potential hatches with an initial temperature above this threshold were temporarily skipped. Compared with open-loop processing, closed-loop control resulted in vertical alignment of columnar prior-β grains, more uniform α-lath widths, and more-uniform microhardness values within the deposited component.
AB - The location, timing, and arrangement of depositions paths used to build an additively manufactured component - collectively called the build plan - are known to impact local thermal history, microstructure, thermal distortion, and mechanical properties. In this work, a novel system architecture for intra-layer, closed-loop control of the build plan is introduced and demonstrated for directed-energy deposition of Ti-6Al-4V. The control strategy altered the build plan in real time to ensure that the temperature around the start point of each hatch, prior to deposition, was below a threshold temperature of 415. °C. Potential hatches with an initial temperature above this threshold were temporarily skipped. Compared with open-loop processing, closed-loop control resulted in vertical alignment of columnar prior-β grains, more uniform α-lath widths, and more-uniform microhardness values within the deposited component.
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U2 - 10.1016/j.addma.2015.03.005
DO - 10.1016/j.addma.2015.03.005
M3 - Article
AN - SCOPUS:84926136471
SN - 2214-8604
VL - 6
SP - 39
EP - 52
JO - Additive Manufacturing
JF - Additive Manufacturing
ER -