High strength low thermal expansion alloy

A high strength low coefficient of thermal expansion alloy having a CTE of about 4.9.times.10.sup.-6 m/m/.degree.C. or less at 204.degree. C., consisting essentially of, by weight percent, about 42.3 to about 46 nickel, about 2.5 to about 3.6 niobium, about 0.9 to about 1.9 titanium, about 0.05 to about 0.8 aluminum, about 0 to about 0.1 carbon, about 0 to about 1 manganese, about 0 to about 1 silicon, about 0 to about 1 copper, about 0 to about 2 cobalt, about 0 to about 0.01 boron, about 0 to about 2 tungsten, about 0 to about 2 vanadium, about 0 to about 0.5 total yttrium and rare earths, about 0 to about 0.1 sulfur, about 0 to about 0.1 phosphorous, about 0 to about 0.1 nitrogen, about 3.6 or less total niobium plus tantalum and balance iron and incidental impurities.

A high strength low coefficient of thermal expansion alloy having a CTE of about 4.9.times.10.sup.-6 m/m/.degree.C. or less at 204.degree. C., consisting essentially of, by weight percent, about 42.3 to about 45 nickel, about 3 to about 3.5 niobium, about 1 to about 1.8 titanium, about 0.05 to about 0.6 aluminum, about 0 to about 0.05 carbon, about 0 to about 0.5 manganese, about 0 to about 0.5 silicon, about 0 to about 0.5 copper, about 0 to about 2 cobalt, about 0 to about 0.005 boron, about 0 to about 1 tungsten, about 0 to about 1 vanadium, about 0 to about 0.1 total yttrium and rare canes, about 0 to about 0.05 sulfur, about 0 to about 0.05 phosphorous, about 0 to about 0.05 nitrogen, about 3.5 or less total niobium plus tantalum, about 0 to about 0.25 tantalum and balance iron and incidental impurities.