Microstructural formation and effects on the performance of platinum modified aluminide coatings
By: by P. Deb, and D.H. Boone
Contributors: Boone, Donald H.; Naval Postgraduate School (U.S.). Dept. of Mechanical Engineering
Publisher: Naval Postgraduate School; Available from National Technical Information Service
Published: 1985
Place of publication: Monterey, Calif; Springfield, Va
Language: eng
Number of pages: 57
Subjects: PLATINUM; ALUMINATES; METAL COATINGS
Other titles: NPS-69-85-008.
Description: The use of noble metal modified aluminide coatings has gained renewed interest as the      requirements of improved protectivity for gas turbine engine components has increased.      Increasing temperature, severity of operating environment and required lifetime extension are      cited as reasons for their selection. While the literature documents examples of significant      improvements in hot corrosion resistance at low (800 C) and high (800 C) temperatures and      in cyclic oxidation with Pt additions, there are also examples of limited improvements and even      detrimental effects. These controversies have been preliminarily ascribed to the considerable      differences in microstructural features possible in these systems and to the variation in test      procedures between laboratories, and between rigs and engines. A systematic study was      therefore initiated to identify the microstructural variations obtained for platinum-modified      aluminide coatings on IN738 and to develop a fundamental understanding of their mechanism      of formation. In this final report, the several classical structural types are defined together with      the beginnings of their formation understanding. These microstructures were then subjects to a      series of tests under conditions including hot corrosion at 700 and 900 C, and cyclic      oxidation. In addition, measurements of mechanical properties such as DBTT were      performed. It was found tha platinum addition to a standard aluminate is beneficial at 900 C,      so far as hot corrosion attack is concerned.
Notes: Title from cover.

"NPS-69-85-008."

"November 1985."

AD A166 166.

Includes bibliographical references (p. 28-30)

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