Electrodeposition of nanocrystalline Ni-W coatings strengthened by ultrafine alumina particles

► Nanocrystalline Ni-W/Al2O3 composite coatings were DC electrodeposited under ultrasonic field. ► We examine different types of Al2O3 nanopowders. ► Al2O3 structure influences composite composition and properties. ► Lower frequencies of ultrasound essentially improved mechanical performance of composite coatings.