Processing and characterisation of ruthenium aluminium alloys
No Thumbnail Available
There is an ever increasing demand for materials usable at high temperatures and under extreme environmental conditions. The power generation sectors and aerospace industries are fostering the development of alternative materials with lower density, high strength and high application temperature. Material development coupled with improvements on the processing technology efforts of the last two decades has resulted in the availability of multi-component alloys with good high-temperature strength and oxidation resistance. However, it seems that the potential of the conventional materials has been exploited to the maximum extent and hence an intensified research is required in this area of newer materials development. Intermetallic alloys have been identified as an emerging class of materials and have been the subject of studies for many years as the potential replacement for the existing high-temperature materials. A large number of intermetallic alloys such as Ni- Al based alloys, Ti-Al based alloys, Fe-Al based alloys, etc. has already been identified for high-temperature applications. However, the lack of a good combination of room temperature ductility and toughness together with high temperature strength and corrosion resistance are some of the major barriers for their application as high temperature structural materials. Hence, the successful development of newer materials based on intermetallic alloys depends on the improvement of these properties. Though intermetallic ruthenium aluminide (RuAl) phase was identified in 1960, its properties amenable for high temperature structural applications have been unveiled only in the early nineties. These reports on the properties of Ru-Al alloys triggered the scientific research on RuAl. Ru-Al alloys exhibit a combination of high ductility and toughness, high strength and corrosion resistance at high temperatures. The intermetallic phase RuAl has a very high melting point (उ 2060 उC). Due to these basic properties, RuAl is considered as a high-temperature structural material. However, there exist quite a few disagreements in the currently available binary and ternary phase diagrams of this alloy system. Past research activities were directed mostly on the Al rich side of the Ru-Al phase diagram, leaving the Ru rich side of the phase diagram relatively unexplored....
Supervisor: P S Robi