Design and Development of Ni-Base Superalloy and Ti Alloys

摘要

This overview article describes what has been done in NRIM for design anddevelopment of Ni base superalloys and Ti alloys of high temperature use. Most of those works were performed in two national projects. For Ni base alloys we have developed alloy design programs in which compositions of two phases, gamma and gamma prime, can be estimated and properties of alloys are described and predicted as functions of the phase compositions and the phase volume fraction. For Ti alloys similar design programs were studied for alpha and beta phases, and later for alpha and alpha(2) phases. For Ni-base alloys, after developing the first version of the design program, we applied this to develop conventionally cast alloys, directionally solidified columnar alloys, single crystal alloys, superplastically workable alloys, and oxide dispersion strengthened alloys. The second version of alloy design program for Ni-base alloys was then developed and was chiefly applied to single crystal alloys. For the above alloy development projects we have proposed a number of new alloys. By using the alloys proposed, process studies were done mainly by companies participating in the projects.