caa a22 4500 388075635 CHVBK 20180307125159.0 cr unu---uuuuu 161130e199904 xx s 000 0 eng 10.1557/S0883769400052143 doi S0883769400052143 pii (NATIONALLICENCE)cambridge-10.1557/S0883769400052143 The Application of CALPHAD Techniques in the Development of a New Gas-Turbine Disk Alloy [Elektronische Daten] The development of a new nickel based superalloy for use in the high-pressure turbine disk of a modern gas turbine is one of the most expensive and protracted exercises undertaken by gasturbine manufacturers. A typical complete development cycle can take more than 10 years. This delay arises not only because of the extensive mechanical testing and Validation required to ensure the safety of the critical part, but also because of the difficulty of finding a material chemistry that provides the correct degree of balance between mechanical properties and long-term material stability. The conventional approach to this latter problem is to use a combination of experience, empirical wisdom, and a few basic calculation tools based on electron-valency theory (PHACOMP). There is thus an urgent need to develop a tool that reliably summarizes the known body of knowledge about the stability of Ni-based superalloys and provides a method that can quickly and reliably guide the alloy developer through the initial alloy-chemistry selection phase of development. Calculation of phase equilibria using calculated phase-diagram (CALPHAD) techniques has now matured to the point where it is possible for the alloy developer to quickly and reliably calculate phase equilibrium in a matter of minutes without an in-depth knowledge of thermodynamics. There thus exists a tool that enables the definition of alloy chemistries so that specific assumptions can be tested and the final chemistry selected without having to carry out the traditional manufacturing, processing, testing, and examination of a large raft of experimental chemistries. This article aims to show how such a tool has been used and high lights the success of this approach in the field of Ni-based superalloy development. Copyright © Materials Research Society 1999 Small C.J. Saunders N. MRS Bulletin Cambridge University Press 24/4(1999-04), 22-26 0883-7694 24:4<22 1999 24 MRS https://doi.org/10.1557/S0883769400052143 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1557/S0883769400052143 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Small C.J. NATIONALLICENCE 700 1- Saunders N. NATIONALLICENCE 773 0- MRS Bulletin Cambridge University Press 24/4(1999-04), 22-26 0883-7694 24:4<22 1999 24 MRS CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge