Cermet alloy composition

Abstract

Abstract A CERMET-TYPE ALLOY POSSESSING IMPROVED SULFIDATION RESISTANCE WHICH IS ADAPTABLE FOR FORMNG PROTECTIVE SURFACE COATINGS ON VARIOUS HIGH-TEMPERATURE, CORROSION-RESISTANT NICKEL, COBALT AND IRON BASE ALLOYS, AS WELL AS SHAPED PARTS OF THE ALLOY PER SE. THE INVENTION ALSO ENCOMPASSES A NOVEL METALLIC POWDER CONTAINING NICKEL AND/OR COBALT IN COMBINATION WITH CHROMIUM FOR FORMING THE CONTINUOUS MATRIX OF THE RESULTANT ALLOY, AS WELL AS TITANIUM AND/OR ZIRCONIUM AS THE REACTIVE METAL CONSTITUENTS WHICH ARE ADAPTED TO UNDERGO AN EXOTHERMIC REACTION WITH BORON UPON FUSION OF THE POWDER MIXTURE AT AN ELEVATED TEMPERATURE IN A SUBSTANTIALLY INERT ATMOSPHERE, THEREBY FORMING THE CORRESPONDING BORIDES OF THE REACTIVE METALS IN SITU, WHICH ARE SUBSEQUENTLY PRECIPITATED AS UNIFORMLY DISPERSED DISCONTINUOUS PHASES IN THE CONTINUOUS PHASE OF THE BASE ALLOY MATRIX. IN ADDITION, THE PARTICULATED MIXTURE FURTHER CONTAINS A CONTROLLED PROPORTION OF A FINELY-PARTICULATED REFRACTORY OXIDE COMPRISED OF ALUMINA WHICH SIMILARLY IS DISPERSED AS DISCRETE PHASES IN THE CONTINUOUS BASE ALLOY MATRIX AT THE COMPLETION OF THE EXOTHERMIC REACTION, FORMING A CERMET-TYPE ALLOY WHICH POSSESSES EXCEPTIONAL RESISTANCE TO SULFIDATION AND OXIDATION ATTACK AT ELEVATED TEMPERATURES.

Inventors

• 👤 Nikolajs Bredzs

Bibliographic Details