Patent ID: 7494617

Claim:
A method for manufacturing a quaternary matrix cobalt-based granular media alloy composition formulated as (Co a Cr b Pt c M′ d ) f 1 -(M u O v ) f 2 , M′ representing an element selected from the group consisting of boron (B), tantalum (Ta), niobium (Nb), zirconium (Zr), copper (Cu), silver (Ag), gold (Au), and ruthenium (Ru), M representing a base metal different from M′ and selected from the group consisting of magnesium (Mg), titanium (Ti), vanadium (V), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), aluminum (Al), silicon (Si), yttrium (Y), zirconium (Zr), niobium (Nb), molybdenum (Mo), ruthenium (Ru), indium (In), lanthanum (La), hafnium (Hf), tantalum (Ta), and tungsten (W), u and v representing the number of atoms of base metal M and oxygen (O) per oxide formula, respectively, a and b representing atom fractions, f 1 and f 2 representing mole fractions expressed by the equation f 1 +(u+v)f 2 =1, and d being represented by the equation d=1−a−b−c, the method comprising the steps of: blending a Co a′ Cr b′ Pt c′ M′ d′ M e′ master alloy powder and a Co u′ O v′ powder into a corresponding (Co a′ Cr b′ Pt c′ M′ d′ M e′ ) f 1 ′ -(Co u′ O v′ ) f 2 ′ , formula, wherein f 2 ′ is represented by the formula: f 2 ′ = v v ′ · f 2 , wherein f 1 ′ is represented by the formula f 1 ′ = 1 - v v ′ ⁢ ( u ′ + v ′ ) ⁢ f 2 , and wherein a′, b′, c′ d′ and e′ are represented by the formulas a ′ = f 1 · a - u ′ · v v ′ · f 2 1 - v v ′ ⁢ ( u ′ + v ′ ) ⁢ f 2 b ′ = f 1 · b 1 - v v ′ ⁢ ( u ′ + v ′ ) ⁢ f 2 c ′ = f 1 · c 1 - v v ′ ⁢ ( u ′ + v ′ ) ⁢ f 2 d ′ = f 1 · d 1 - v v ′ ⁢ ( u ′ + v ′ ) ⁢ f 2 e ′ = f 2 · u 1 - v v ′ ⁢ ( u ′ + v ′ ) ⁢ f 2 ; and densifying the blended powders.