S044015 Effect of Spray Angle on Adhesion Strength of Aluminum Coating and Particle Impact Behavior on Ceramic Substrates in Cold Spray

Abstract

Coating adhesion is a critical factor on coating technology. However, the adhesion mechanism of cold sprayed metallic coating on ceramic substrate has not understood sufficiently yet Therefore, there is a limitation to apply cold sprayed coating to industrial products, such as power electronic components. Generally, shear localization that occurs at the interface between a particle and a substrate during particle impact has a notable effect on adhesion strength of cold sprayed coatings. In this study, spray angle is focused to improve the shearing area and force. And also, the effects of spray angle, substrate hardness and surface roughness on adhesion strength of aluminum coatings were investigated. The spray angle was varied to two different levels: 60 and 90 degree. Used substrate materials were ceramics Al_2O_3 and Si_3N_4 and soda glasses. In addition, morphologies of individual aluminum particles was observed. As a result, the adhesion strength of the aluminum coating on Al_2O_3 and Si_3N_4 substrates increased in case of the spray angle of 60 degree. Then, it is shown that the adhesion strength of the aluminum coating on the Al_2O_3 substrate is higher than that on the Si_3N_4 substrate. The morphologies of a single aluminum particle varied depending on the spray angle.