Consolidation of TiAl Powder by Thermal Spray Processes
Thermal spray deposition has been widely used as a coating process for applying thin protective layers to the need-to-protect materials, or substrates. Recent technological developments in thermal spray processing, particularly cold gas spraying (CGS) and supersonic plasma spraying (S-PS), have enabled some emerging applications for making structural components. This paper reports on the results of our recent attempts to obtain thick TiAl coatings using three coating techniques: atmospheric plasma spraying (APS), S-PS and CGS. We successfully achieved a 3 mm thick coating using both APS and S-PS techniques, but failed in cold spray. A significant phase change was observed of the powder particles experienced during both APS and S-PS processes. Nevertheless, a considerable quantity of titanium oxides was observed in the APS coating.
Deliang Zhang, Kim Pickering, Brian Gabbitas, Peng Cao, Alan Langdon, Rob Torrens and Johan Verbeek
P. Cao et al., "Consolidation of TiAl Powder by Thermal Spray Processes", Advanced Materials Research, Vols. 29-30, pp. 159-162, 2007