In this study three Ni-Al-Cr-C nickel based casting alloys with 0.5, 1.0 and 1.5wt% carbon content were processed by spray forming aiming, to investigate the potential of achieving substantial microstructure refinement by the high cooling rate involved in this process. Some attempts were done in order to evaluate the wear resistance of these alloys by means of pin-on-disk tests. Two values for the gas to the metal flow rate ratio, GMR, were used ( 0.12 and 0.23) and nitrogen was used as the atomization gas. The overspray powders and the deposit were characterized by using optical and scanning electron microscopy. The high cooling rate resulted in a strong microstructural refinement, with carbides of about two order of magnitude smaller than those obtained in the conventionally cast materials, dispersed in a predominantly gamma-prime matrix. Higher GMR led to a more refined microstructure due to higher cooling rate imposed to the atomized droplets. The microstructure observed in the deposit could be correlated with that observed in the overspray powders, indicating transformations during deposition process. The atomized alloys having higher carbon content (1.5%) and consequently higher volumetric fractions of carbides, presented better wear resistance. Their results are similar or slightly better than those obtained for a conventionally cast high chromium white cast iron.