Impact phenomena in cold-spraying of titanium onto various ferrous alloys

The impact and deformation behaviour of particle and substrate in cold-spraying is dictated by the high strain rate materials behaviour which affects bonding. In this study, titanium particles have been deposited onto three different ferrous alloy substrates, namely low carbon steel, an Armco iron, and an austenitic stainless steel. The deformation behaviour of the particle-substrates was characterised by scanning electron microscopy and modelled using Johnson-Cook material parameters at high strain rate. Localised deformation of the Armco iron was observed following deposition of titanium particles, whereas a combination of particle-substrate deformation was observed in titanium-low carbon steel and titanium-austenitic stainless steel. The chemical composition i.e., carbon content of the substrate alters the high strain rate deformation behaviour upon cold spraying. Jetting of titanium particles was observed following deposition onto low carbon steel and austenitic stainless steel while restricted jetting of titanium particles following deposition onto Armco iron was observed as the particles were embedded into the Armco iron. (C) 2011 Elsevier B.V. All rights reserved.