Abstract: A nickel-chromium alloy exhibiting enhanced stress rupture strength and grain size stability at elevated temperatures up to about 1260.degree. (2300.degree. F.) due to the affirmative formation of M.sub.6 C carbide within the alloy. The alloy is especially useful for turbine and engine applications.

Abstract: Nickel-base, high chromium alloys characterized by good sulfidation and oxidation resistance consisting essentially of about 27 to 35% chromium, about 2.5 to 5% aluminum, about 2.5 to about 6% iron, 0.5 to 2.5% columbium, up to 0.1% carbon, up to 1% each of titanium and zirconium, up to 0.05% cerium, up to 0.05% yttrium, up to 1% silicon, up to 1% manganese, balance nickel.

Abstract: The stress-rupture strength of a nickel-chromium-molybdenum-cobalt alloy is enhanced by reason of a special morphological microsctructure which in terms of carbides present is characterized by a predominant amount of the M.sub.6 C carbide.

Abstract: A high-nickel-chromium iron alloy containing aluminum and titanium is particularly useful under high temperature/oxidizing conditions such as encountered in ceramic tile industry frit-firing applications. The alloy also contains a special percentage of nitrogen as well as zirconium.

Abstract: An oxidation resistant nickel-chromium based alloy possessing good stress rupture characteristics at elevated temperature and, in addition to nickel and chromium, containing correlated percentages of aluminum, titanium, nitrogen, carbon, etc.

Abstract: A carburization-resistant alloy comprising in weight percent about 50 to about 55% nickel, about 16 to 22% chromium, about 3 to about 4.5% aluminum, up to about 5% cobalt, up to about 5% molybdenum, up to about 2% tungsten, about 0.03 to about 0.3% carbon, up to about 0.2% rare earth element, balance essentially iron. The alloy is useful for structures, objects, parts etc. which are exposed in use to carburizing atmospheres and which, periodically are subjected to oxidizing atmospheres. For example the alloys are useful for pyrolysis tubes used in the petrochemical industry which must periodically be subjected to oxidizing atmospheres to burn-out carbon deposits and which, during pyrolysis are in contact with atmospheres having log Po.sub.2 spanning at least the range of -17 to -26 and which exist at various temperatures.

Abstract: A composite tube structure having an inner substrate alloy and an outer, corrosion resistant alloy suitable for use in fluid-bed coal combustion reactors to form a water wall around at least a portion of the periphery of the fluid bed zone. The outer, corrosion resistant alloy centers around a composition of 0.1% carbon, 0.2% silicon, 0.5% manganese, 22% chromium, 3.8% aluminum, 0.4% titanium, 0.05% nitrogen, 0.2% molybdenum, 32% nickel, balance iron.