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Title: Zirconia-Toughened Alumina Coated Ti6Al4V via Additive Manufacturing
Processing and characterization for zirconia toughened alumina (ZTA) coatings on Ti6Al4V (Ti64) alloy by directed energy deposition (DED)-based additive manufacturing (AM) is presented here. The objective of the study was to achieve a dense ZTA coating with the intent of providing an alternative to fully ceramic implants for articulating surfaces of total hip arthroplasty (THA). Preliminary work resulted in failed samples due to cracking, porosity, and delamination. After careful parameter optimization, a Ti64+5wt.%ZTA (5ZTA) composition produced a metallurgically sound and coherent coating with minimal porosity. Additionally, bulk structures were also feasible with the optimized coating parameters. Characterization of the 5ZTA composition displayed a 27.0% increase in hardness, 25% reduction in normalized wear rate, an increase in contact resistance during in vitro tribological testing along with a faster surface re-passivation post-tribological testing.  more » « less
Award ID(s):
1934230
PAR ID:
10282716
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Materials letters
Volume:
129577
ISSN:
0167-577X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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