Abstract
This study employs a combination of numerical analysis and experimental testing to obtain a better understanding of the changes that occur in hollow spherical metal-oxide powders during detonation spraying and how they affect coating quality. The heating and melting characteristics of hollow spheres are initially calculated for the general case then refined based on a simple detonation spraying model. The estimates are compared with experimental results obtained from detonation-sprayed Al2O3 coatings produced using fused and crushed, dense spherical, and hollow spherical powders. The coatings as well as the powders are characterized based on morphology, particle size distribution, splat formation, cross-sectional microstructure, porosity, and hardness. Important findings, observations, and correlations are identified and discussed in the paper.
