Abstract
The demand for highly continuous thermal spray deposition processing to gain manufacturing efficiency and enhanced control of deposition microstructure has driven the search for powder feedstocks that exhibit uniform flow behavior in pneumatic feeding devices even at low carrier gas flow ratios. This paper compares the continuous powder feeding characteristics of one type of feeding device for two different powder alloys fabricated by a representative set of powder processing methods, including spray dried, fused (cast) and crushed, and inert gas atomized. Powders were fabricated by both commercial vendors and Ames Laboratory processing equipment. The powder mass flow rate was found to depend directly on the apparent density of a specific powder type instead of the dry powder flowability, as initially expected.