Effect of nozzle configuration, gas pressure, and gas type on coating properties in wire arc spray

• Published in: Journal of thermal spray technology Vol. 8; no. 4; pp. 565 - 575
• Main Authors: WANG, X, HEBERLEIN, J, PFENDER, E, GERBERICH, W
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01-12-1999
• Subjects: Adhesion; Applied sciences; Arc spraying; Atomization; Atomizing; Coating; Exact sciences and technology; Fluid dynamics; Gases; Metallic coatings; Metals. Metallurgy; Nozzles; Porosity; Pressure effects; Production techniques; Protective coatings; Shrouds; Sprayers; Sprays; Substrates; Surface treatment; Wire; Particle size; Aluminium base alloys; Arc spraying; Hardness; Adhesion; Spray coating; Surface treatment; Metal coating; Pressure effect; Stainless steel; Porosity; Atomization; Microstructure
• ISSN: 1059-9630; 1544-1016
• DOI: 10.1361/105996399770350269

Wire arc spraying is a coating process in which minor modifications of the configuration and spray parameters can have a strong impact on coating characteristics. A study on the effects of the fluid dynamics of the atomizing gas on the coating properties is presented. Different types of nozzles, shrouds, and gases have been used to provide various flow velocities and reactive environments in the metal atomization region. The effects on particle velocity, coating density, composition, and interface characteristics between the coating and the substrate have been evaluated. It is clear that higher gas velocities improve practically all coating properties, but also increase oxide content in the coating. However, the oxidation can be drastically reduced if nonoxidizing gases are used for atomization in combination with a shroud. A discussion on the physical effects contributing to the observed adhesion improvements and interfacial properties is provided.