Study of Relationship Between Titanium Powder Structure and Cold Spray Deposit

  During Cold Spray small powder particles are propelled to supersonic velocities in a heated nitrogen gas stream using a converging-diverging Laval nozzle. Particles bond to the substrate on impact to form a strong metallurgical bond, however, little is understood regarding the effects of process gas temperature on the deposited titanium structure. In this study the relationship between titanium powder and deposited layer composition and structure were investigated. Cold Spray depositions were produced at process gas temperatures of 400°C, 600°C, and 800°C. Determination of trace oxygen, nitrogen, and hydrogen was studied using Synchrotron Powder Diffraction beamline, Leco oxygen-nitrogen-hydrogen analyser, scanning electron microscopy, x-ray diffraction, and optical microscopy.