A metal-matrix material in the form of a carbide powder together with a sodium fluoride flux is deposited as a charge within a crucible for induction heating thereof to a flux melting temperature to thereby initiate pretreatment. The molten flux is spread over and covers powder particles of the metal-matrix carbide throughout, in response to stirring by rotation of an agitator during said flux melt heating within the crucible. The charge may be covered within the crucible by an air-purging blanket of argon gas during said heating. The powder fluxed charge is then cooled within the crucible before removal therefrom and sealingly packaged within aluminum soda cans or foil wrappings for future use storage. Such packaged charges are transferred from storage and introduced into a casting mold for enhanced centrifugal cast molding of metallurgical products, such as a metallic ring having an outer carbide bronze surface.