Abstract
Over the past five years, interest in cold gas dynamic spraying (CGDS) has increased substantially. Considerable effort has been devoted to process development and optimization for low melting point metals such as copper and aluminium. This paper will describe work undertaken to expand the understanding of deposition of titanium by cold spray methods. CGDS deposits have been produced from commercially pure Ti. Using room temperature helium gas, a range of processing conditions, powder size ranges, substrates and substrate preparation methods have been employed to study their impact on deposition of powders. Scanning electron microscopy has been employed to examine deposit microstructures, and microhardness testing of deposits has been conducted. Samples for pull-off bond strength test have been prepared from a number of the more promising sets of parameters and adhesive strengths have been determined. Computational estimates of gas velocity and in-flight particle velocity have been made focusing specifically on the influence that these factors have on the process deposition efficiency. Differences will be discussed in terms of powder feedstock characteristics and the underlying physical and mechanical properties of the powders and substrates.
