Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Desulfurization of Ni-based super alloys by combined heating and glow discharge

Journal Article · · Scripta Materialia
 [1];  [2];  [3];  [4]
  1. National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center
  2. Old Dominion Univ., Norfolk, VA (United States)
  3. United Technologies Research Center, East Hartford, CT (United States)
  4. Massachusetts Inst. of Tech., Cambridge, MA (United States)

The service lifetime of blades and vanes in aircraft gas turbines can be influenced by the degradation of the interface of the Ni-based superalloy and the overlying aluminide coating during cyclic oxidation. Advanced superalloys and coatings rely on formation of a thin and continuous Al{sub 2}O{sub 3} film to protect the base alloy from further oxidative attack at temperatures above 980 C. In order that the Al{sub 2}O{sub 3} scale be protective, it must remain adherent to the underlying alloy under thermal cycling conditions. Recent experimental work indicates that the interfacial binding between Ni and the overlying Al{sub 2}O{sub 3} scale is initially strong, but has also been shown that segregation of indigenous sulfur to the metal/oxide interface induces premature scale spallation, apparently through a reduction in the interfacial adhesive strength with a concomitant reduction in component lifetime. Removal of the sulfur is the best solution to this problem.

OSTI ID:
230770
Journal Information:
Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 8 Vol. 34; ISSN 1359-6462; ISSN XZ503X
Country of Publication:
United States
Language:
English