Patent ID: 8491696

Claim:
A process for producing ultrafine alloy particles made of an alloy consisting essentially of a primary metal and two or more subsidiary metals, comprising the steps of: introducing powder materials for producing said ultrafine alloy particles into a thermal plasma flame under reduced pressure to form a vapor-phase mixture, said powder materials including said primary metal and said two or more subsidiary metals solid-soluble in said primary metal and a content of said two or more subsidiary metals being in a range of 1 wt % to 25 wt %; and introducing a cooling gas toward an end portion of said thermal plasma flame in a supply amount sufficient for quenching said vapor-phase mixture so as to generate said ultrafine alloy particles capable of inhibiting coalescence or oxidation, or both, of said ultrafine alloy particles consisting essentially of said primary metal and said two or more subsidiary metals, wherein said two or more subsidiary metal impart function of coalescence-inhibition or oxidation-inhibition, or both, to said ultrafine alloy particles, when said two or more subsidiary metals form said ultrafine alloy particles with the primary metal, and wherein powder materials have a particle size of 3 μm to 10 μm, and said ultrafine alloy particles have an average particle size of 1 nm to 100 nm.