Influence of Gas Temperature and Heat Treatment on Microstructure and Properties of Cold Sprayed Commercially Pure Titanium

Diffusion of oxygen and nitrogen in the cold sprayed commercially pure Ti (CS CP Ti) deposits profoundly impacts their mechanical properties. One plausible approach to additively manufacture a malleable (wrought) and high-density Ti is optimizing CS deposition parameters considering a reduction in porosity for the following heat treatment. Herein, we examined porosity, bulk density, and hardness characteristics of CS CP Ti deposits produced at varying processing gas temperatures (700, 800, and 900 degrees C), which significantly influences the interactions of CP Ti with oxygen and nitrogen. Post-processing heat treatments at 800, 900, and 1000 degrees C were performed in a high vacuum furnace, respectively, which diminished splat boundaries and submicron pores with increasing grain size. SEM images revealed that CS CP Ti had a dense microstructure with low porosity. According to LECO research, low spraying temperatures (i.e. 700 degrees C) maintained oxygen and nitrogen levels in the CS CP Ti deposits at the same level as the stock powders. The bulk density of CS CP Ti produced at 900 degrees C matched that of wrought CP Ti metal. In addition, to improve the mechanical properties of CS CP Ti deposits, we looked at the link between CS conditions and heat treatment.

Automated summary

The diffusion of oxygen and nitrogen in cold sprayed titanium deposits significantly affects their mechanical properties. By optimizing deposition parameters and conducting heat treatment, a malleable and high-density titanium material can be obtained.