| Abstract | In this study, a 43 μm 316L stainless steel and a 23 μm commercial purity Fe feedstocks were used. The following coatings were made by cold spray: single component 316L, Fe, and their binary composites with nominal compositions of 20 wt.% Fe (20Fe), 50 wt.% Fe (50Fe) and 80 wt.% Fe (80Fe). The coatings were characterized (microstructure, flattening ratio, composition) and the cold sprayability metrics (DE, porosity, bond strength) were analyzed. Results show that the single component 316L coating has a much better DE and bond strength, and a slightly lower porosity as compared with the Fe coating. Whereas all the composite coatings have the similar bond strength. Moreover, the 20Fe coating features the highest porosity and the lowest DE; 50Fe coating features the lowest porosity; and the 80Fe coating features the highest DE. To indicate the feedstock mixture composition, in addition to the routine approach such as weight or volume fraction, the particle number ratio of the large/small components, which is defined as the ratio of the numbers of the component particles in a mixture estimated by the mean particle size, was calculated. Using this metric, the effects of the feedstock mixing composition on the cold sprayability of bimodal size 316L/Fe powder mixtures can be better explained. |
|---|
