A Platinum-Enriched gamma+gamma' Two-Phase Bond Coat on Ni-Base Superalloys

Journal Article · Sat Jan 01 04:00:00 EST 2005 · Surface and Coatings Technology

DOI:https://doi.org/10.1016/j.surfcoat.2005.07.086· OSTI ID:930695

Zhang, Ying ^[1]; Pint, Bruce A ^[2]; Haynes, James A ^[2]; Wright, Ian G ^[2]

---

1. Tennessee Technological University
2. ORNL

Pt-enriched {gamma} + {gamma}{prime} two-phase coating was applied to directionally-solidified Ni-based superalloy Ren{acute e} 142 substrates with three different Hf levels (0.02, 0.76, and 1.37 wt.%). The coating was prepared by electroplating a thin layer of Pt on the superalloy followed by a diffusion treatment. The as-deposited coating exhibited a {gamma} + {gamma}{prime} two-phase microstructure with a major composition of Ni-16Al-18Pt-7Cr-9Co (in at.%) along with some incorporation of refractory elements from the substrates. Cyclic oxidation testing at 1100 C in air indicated improved oxidation resistance of the Ren{acute e} 142 alloys with the Pt-enriched {gamma} + {gamma}{prime} coatings. In addition, the oxidation resistance of both uncoated and coated alloys was proportional to the Hf content in the substrate. Compared with the single-phase {beta}-(Ni,Pt)Al coating, slightly higher mass gains and localized spallation were observed on the {gamma} + {gamma}{prime} two-phase coating, which might be due to the segregation of refractory elements and high sulfur levels in these superalloy substrates.

• Research Organization: Oak Ridge National Laboratory (ORNL); Shared Research Equipment Collaborative Research Center
• Sponsoring Organization: FE USDOE - Office of Fossil Energy (FE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 930695
• Journal Information: Surface and Coatings Technology, Journal Name: Surface and Coatings Technology Vol. 200; ISSN 0257-8972; ISSN SCTEEJ
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALLOYS
COATINGS
DIFFUSION
ELECTROPLATING
HEAT RESISTING ALLOYS
MICROSTRUCTURE
OXIDATION
SEGREGATION
SPALLATION
SUBSTRATES
SULFUR
TESTING