Processing and characterization of plasma-sprayed ceramic coatings on steel substrate: Part II. On coating performance

• Published in: Metallurgical and materials transactions. A, Physical metallurgy and materials science Vol. 34; no. 9; pp. 1919 - 1930
• Main Authors: DAS, S, BANDYOPADHYAY, P. P, GHOSH, S, BANDYOPADHYAY, T. K, CHATTOPADHYAY, A. B
• Format: Journal Article
• Language: English
• Published: New York, NY Springer 01-09-2003; Springer Nature B.V
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Mechanical and acoustical properties; Metals. Metallurgy; Nonmetallic coatings; Physical properties of thin films, nonelectronic; Physics; Production techniques; Surface treatment; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Scanning electron microscopy; Thermal cycle; Thermal fatigue; Steel; Hardness; Experimental study; Coatings; Adhesion; Spray coating; Surface treatment; Zirconia; Fatigue strength; Adhesion test; Plasma spraying; Alumina; Ceramic materials; Fractography
• ISSN: 1073-5623; 1543-1940
• DOI: 10.1007/s11661-003-0157-2

This investigation envisages the performance evaluation of a series of plasma-sprayed coatings from a few inexpensive powders, namely, alumina, plasma dissociated zircon (PDZ), zircon sand, and zircon-20 wt pct calcia. The hardness and adhesion (bond) strength of the coatings have been evaluated. All coatings offer an attractive thermal fatigue property. An added layer of yttria between the top and bond coats improves the thermal fatigue resistance appreciably. The wear performance of these coatings has also been evaluated using a "pin-on-disc" type wear testing setup. The Indian alumina coating offers a superior wear resistance and thermal fatigue property compared to an imported alumina coating. The coatings based on zirconia-silica offer an attractive thermal fatigue resistance along with an acceptable wear resistance. The latter improves considerably upon annealing of the coatings because of the removal of the residual stresses accumulated during deposition. Among these zirconia-silica-based coatings, the zircon-20 wt pct calcia is the most promising. The finishability of these coatings has been studied using a surface grinding setup equipped with a diamond wheel. The cutting forces and the surface roughness of the ground surface have been measured. The coatings have been found to possess a reasonably good grindability. [Substrate: mild steel.]