Effect of nanocrystallization on the oxide formation of Ni-5Cr-5Al alloy

• Published in: Journal of materials science letters Vol. 18; no. 23; pp. 1957 - 1959
• Main Authors: CHEN, G. F, LOU, H. Y
• Format: Journal Article
• Language: English
• Published: Dordrecht Kluwer Academic Publishers 01.12.1999
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Metals. Metallurgy; Nanoscale materials and structures: fabrication and characterization; Oxidation; Physics; Solid-fluid interfaces; Surface treatments; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Crystal growth; Nickel base alloys; Atomic force microscopy; Ternary alloys; Surface treatments; XRD; Chromium alloys; Experimental study; Coatings; Superalloys; Thin films; Aluminium alloys; Oxidation; SEM; Nanocrystal; Transition element alloys
• ISSN: 0261-8028
• DOI: 10.1023/A:1006657904501

The oxidation resistance of Ni-based superalloys is improved through nanocrystallization. The improvement in oxidation was attributed to the promotion of selective oxidation of Al producing an external layer of Al sub(2)O sub(3) and the improvement of the adhesion between oxide scales and base metal through nanocrystallization. Nanocrystallization could alter Ni-20Cr-2Al from Cr sub(2)O sub(3)-forming alloy to Al sub(2)O sub(3)-forming alloy. Therefore, the boundaries between various oxide types in the oxide map of Ni-Cr-Al with normal-grained could be changed through nanocrystallization. A Ni-Cr-Al ternary alloy with both low Cr and low Al contents was developed and its nanocrystalline coating was produced, the oxide formation of nanocrystalline coating was investigated.