Liquid Dynamic Compaction (LDC) is a two-stage powder metallurgy process comprising inert gas atomization followed by deposition of the variously sized droplets produced on a suitable substrate surface. The paper describes the effects of process parameters, mainly gas pressure, on the microstructure of a spray-deposited Zn-4Al-1Cu alloy using optical microscopy and scanning electron microscopy. This alloy exhibited very interesting and unpublished variations in its microstructure, which had well defined equiaxed grains of primary zinc-rich phase (eta) embedded in a fine eutectoid phase alpha + eta, resulted from the eutectic decomposition beta + eta. at 275 degrees C. The results showed that the microstructures of the deposits are quite different from those presented in the droplets. To estimate the solidification rates of the alloy obtained in this work, it was cast in a wedge-shaped cast-iron chill mold. This technique allows important predictions to be made without having to perform gas atomization-deposition.