Near-Net-Shape Forming of Ti-6Al-4V Alloy by Vacuum Plasma Spraying

Recently, vacuum plasma spray forming (VPSF) has been§identified as a process capable of manufacturing§near-net-shape components for advanced technology§applications such as aerospace, defense, and chemical§process industries. By optimizing the deposit§structure via intelligent control of process§parameters and utilizing post-deposition heat§treatments, deposit structures with properties better§than conventionally cast materials and, in some§cases, equivalent to wrought materials can be§produced. In this study, VPSF process has been§employed to form near-net-shape structures of one of§the most important and widely used titanium alloys,§Ti-6Al-4V. Since the quality requirements for sprayed§structural materials are different than those for§coatings, characterization of the standard coating§parameters does not fully address the microstructure§requirements that must be met to assure optimal§properties. The initial powder, as-sprayed structure§and splat formation of the alloy during thermal spray§process were investigated comprehensively in this§study. Three heat treatment cycles were developed to§achieve desired physical and mechanical properties of§the VPS deposited material.