ISSN: 1945-7553
Published Online: 22 March 2006
Page Count: 3

Evaluation of Adhesive Strength of Thin Plasma Sprayed Oxide Coatings by a Crosshatch Testing Method

Venkataraman, R
Research Fellow, MST Division, National Metallurgical Laboratory, Jamshedpur,

Sampath Kumar, TS
Professor, Indian Institute of Technology-Madras, Chennai,

Ramalingam, K
Professor, Indian Institute of Technology-Madras, Chennai,

(Received 14 March 2005; accepted 15 February 2006)

Abstract

A test method for the evaluation of the adhesive strength of coatings of thickness less than 250 µms has been attempted on coupons of pure alumina and alumina-13 wt% titania samples plasma sprayed on low alloy steel substrates. Crosshatches were made with a diamond tipped wheel with 0.02-mm width and 20-mm bore diameter, which was mounted on a common tooling and grinding machine. Cuts with 5×5 mm were made on the as-sprayed surface; subsequently, a pressure-sensitive tape was applied on the hatched surface and pulled off. The area of the coatings thus removed was interpreted in accordance with ASTM D 3359B testing standard; the testing method seems to be appropriate for qualitative evaluations.

Keywords:
plasma spraying, adhesive strength measurements, ASTM C 633, ASTM D 3359, crosshatch testing

Paper ID: JTE14100
DOI: 10.1520/JTE14100
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