Influence of powder characteristics on the microstructure and bond strength of cold-sprayed aluminum coating

Pierre-Emmanuel Leger (1) , François Borit (1) , Nicole Fabregue (1) , Michel Jeandin (1) , M. Ducos

1 CDM - Centre des Matériaux

Cold spray aluminum coatings are today developed for a wide range of applications such as the repair of aircraft components, or additive manufacturing. However, powders specifically tailored for cold spray, are yet not available due to a rather low amount of results on the effect of powder characteristics on cold spray coatings properties. The influence of powder morphology on the microstructure and bond strength of cold-sprayed aluminum coating is shown in this study. Aluminum powders with spherical and irregular particle shapes were selected and cold-sprayed onto shot-peened steel. These powders were mixed with two alumina powders with either a spherical or an angular particle shape to improve coating properties. The effect of powder characteristics on coating microstructure was studied using X-Ray diffraction, optical and scanning electron microscopy. In addition, coating adhesion properties were determined using conventional pull-off testing. Aluminum coatings with extremely high adhesion were successfully cold-sprayed on steel. Alumina addition reduced the porosity and increased the hardness of the aluminum coating. Aluminum-alumina mixtures with the same particle shape seem to be more suitable to obtain dense coatings on steel with a high bond strength

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Pierre-Emmanuel Leger, François Borit, Nicole Fabregue, Michel Jeandin, M. Ducos. Influence of powder characteristics on the microstructure and bond strength of cold-sprayed aluminum coating. ITSC 2016, DVS, May 2016, Shanghai, China. 6 p. ⟨hal-01337708⟩