The Platinum Development Initiative: Platinum-Based Alloys for High Temperature and Special Applications: Part III

Under the Platinum Development Initiative, platinum-based alloys were being developed for high-temperature and special applications for good corrosion and oxidation resistance. Work on ternary alloys had previously identified that the best of these systems for both mechanical properties and oxidation resistance were Pt₈₆:Al₁₀:Cr₄ and Pt₈₆:Al₁₀:Ru₄ (1), although the maximum precipitate volume fraction was only ∼ 40% as opposed to ∼ 70% achieved in nickel-based super alloys. Since Pt₈₆:Al₁₀:Cr₄ and Pt₈₆:Al₁₀:Ru₄ gave the best results, a range of quaternary alloys were also made, using these compositions as a basis. The optimum composition was found to be around Pt₈₀:Al₁₄:Cr₃:Ru₃. Subsequently, further additions were made to the quaternary alloys to change selected properties.