Hardness, thermal stability and yttrium distribution in nanostructured deposits obtained by thermal spraying from milled—Y2O3 reinforced—or atomized FeAl powders

The hardness and thermal stability of nanostructured and microstructured deposits obtained by thermal spraying techniques (Atmosphere Plasma Spraying (APS) and High Velocity Oxy-Fuel (HVOF)) from milled (Y2O3 reinforced) or atomised FeAl feedstock powders were investigated. The thick deposits are stable up to about 600 °C; temperature from which significant structural evolution is witnessed by hardness modifications. Though the presence of nanostructure has a significant effect to modify hardness, the results also indicate that the Y2O3 reinforcement incorporated in the feedstock milled powders has little effect on these properties. This is due to the fact that because of lack of miscibility, yttrium was washed away from the melted areas of the deposits.