New Functional Co-base Alloys-Phase stability and Its Industrial Applications

点击翻译按钮获取中文摘要

Thermodynamic database on Co-base alloys has been constructed based on the experimental determinations and thermodynamic assessments by Calphad (Calculation of Phase Diagrams)approach. Using this database, a new type of Co-base superalloys strengthend by the L1_2 compound of γ' Co_3(Al, W)phase has been designed. The developed wrought Co-base superalloy shows the expected creep strength of 100MPa at 800 oC for 10^5 hours, while the cast Co-base superalloy has been applied to the FSW (Friction Stir Welding)tool for practical use. It is shown that the Co-W thin film and Co-based Heusler alloys are attracted for magnetic recording media and spin electronics, respectively. Furthermore, the optimum conditions for compositions and heat treatment to form porous structure on the surface to develop drug eluting stent have been obtained by microstructural control of γ (fcc)/β (B2)lamellar structure of Co-Al-based alloys.