Intermetallic compounds?A new base for heat-resisting materials

Abstract

1. Intermetallic compounds form a special class of inorganic compounds which is promising as a source of heat-resisting materials. They have many properties which are characteristic of metals—mechanical, physical, chemical, and others. 2. Intermetallic compounds have higher melting points than their constituents, higher strength, and retain their heat resistance up to higher temperatures than metals and their solid solutions. 3. Many intermetallic compounds have a high thermal stability and resistance to corrosive media, and can therefore be used as protective coatings for metals and alloys easily oxidized on heating. 4. Intermetallic compounds can interact between themselves. The principles of the formation of intermetallic solid solutions and compounds of complex composition have been determined. 5. The variation of the properties with the composition follows Kurnakov's rules, but the properties of intermetallic compounds may be tens of times higher than those of solid solutions of metals. 6. Certain intermetallic compounds have ductile properties permitting hot and even cold working. These include Ni3Ti, NiTi, Ti3Al, TiAg, etc. 7. With different compositions of precipitation-hardening alloys based on intermetallic solid solutions, a considerable increase in the strength and heat resistance of these materials is possible. 8. Intermetallic compounds and alloys based on them can be used for creating heat-resisting, thermally stable materials. New alloys based on Ni3Al and Ti3Al are very promising.