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Summary: Acta Materialia 50 (2002) 643651
www.elsevier.com/locate/actamat
Chemical ordering and texture in Ni25 at% Al thin films
G.B. Thompson, R. Banerjee, X.D. Zhang, P.M. Anderson, H.L. Fraser *
Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210, USA
Received 14 December 2000; received in revised form 28 August 2001; accepted 28 August 2001
Abstract
This paper describes a novel study of the microstructural development in sputter-deposited thin films from a target
of the intermetallic compound Ni3Al. Films were deposited on oxidized Si substrates at different temperatures, namely
45°C, 200°C, and 400°C. These films have been characterized by X-ray diffraction and transmission electron
microscopy. In contrast to the behavior of sputter-deposited elemental metals and disordered alloys, the films deposited
at the two higher temperatures consisted of refined microstructures and exhibited a low degree of texturing. This
anomalous behavior has been explained by the role of exothermic heating accompanying chemical ordering. 2002
Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.
Keywords: Sputtering; Thin films; Intermetallic compounds; Phase transformations (ordering); Recrystallization & recovery
1. Introduction
In recent years, thin film coatings have been of
considerable interest for their potential use in high
temperature aerospace applications. For example,
thermal barrier coatings of Yittria stabilized Zir-
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