Synthesis of Cu-Coated Ni-Based Amorphous Composite Powders by Gas Atomization and Spray Drying Process

Ni59Zr20Ti16Si2Sn3 bulk metallic glass (BMG) powders were produced by a gas atomization process, and ductile Cu powders were coated on the Ni-based BMG powders using a spray drying process in order to increase the ductility. Characteristics of the as-prepared powders with the atomization and spray drying process conditions were investigated. The atomization was conducted at 1450oC under the vacuum of 10-2 torr and the powders were mixed with water-soluble Cu nitrate. The mixture was sprayed at the temperature of 130oC to prepared initial powder. After reduction treatment, sub-micron size Cu powders were successfully coated on the surface of the atomized Ni BMG powders.