Thermal modeling of plasma spray deposition of nanostructured ceramics

• Published in: Journal of thermal spray technology Vol. 8; no. 2; pp. 315 - 322
• Main Authors: AHMED, I, BERGMAN, T. L
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.06.1999
• Subjects: Applied sciences; Ceramic coatings; Ceramics; Coating; Exact sciences and technology; Heat resistance; Heat transfer; Mathematical models; Melting; Metals. Metallurgy; Nanocomposites; Nanomaterials; Nanostructure; Nanostructured materials; Nonmetallic coatings; Plasma heating; Production techniques; Solidification; Sprayed coatings; Sprayers; Sprays; Substrates; Surface treatment; Austenitic stainless steel; Hot spraying; Nanostructure; Stabilized zirconia; Non metal coating; Modeling; Surface treatment; Solidification; Stainless steel-302; Plasma spraying; Alumina; Ceramic materials; Heat transfer
• ISSN: 1059-9630; 1544-1016
• DOI: 10.1361/105996399770350539

A thermal model for plasma spray deposition of ceramic materials onto metallic substrates has been developed. The enthalpy-based control volume formulation of the heat transfer processes has been used to study the temperature evolution in a two-dimensional substrate and in the coating as it is grown. In this paper, additional melting of ceramic splats after deposition is examined, with a view to predicting the retention of nanostructures in a spray consisting of agglomerated, nanometer-sized particles. Initial results for thin coatings indicate that when the mean temperature of the incoming particles is close to the fusion point of the ceramic material, the nanostructure distribution in the coating is largely determined by the composition of the spray. However, with thicker coatings, additional melting due to prolonged plasma gas heating combined with increased thermal resistance in the underlying coating leads to a loss of nanostructure.