Haynes International, Inc.

Lee M Pike, Jr

Dwaine L Klarstrom

Michael F Rothman

A wrought age-hardenable nickel-chromium-cobalt based alloy suitable for use in high temperature gas turbine transition ducts possessing a combination of three specific key properties, namely resistance to strain age cracking, good thermal stability, and good creep-rupture strength contains in weight percent 17 to 22 chromium, 8 to 15 cobalt, 4.0 to 9.1 molybdenum, up to 7 tungsten, 1.39 to 1.65 aluminum, 1.50 to 2.30 titanium, up to 0.80 niobium, 0.01 to 0.2 carbon, up to 0.01 boron, up to 3 iron, up to 1.5 tantalum and less than 0.02 zirconium, with a balance of nickel and impurities. Certain alloying elements must be present in amounts according to two equations here disclosed.

Ni-Cr-Co alloy for advanced gas turbine engines

A nickel-chromium-molybdenum alloy capable of being age hardened for improved strength while maintaining high corrosion resistance contains in weight percent 19.5 to 22 chromium, 15 to 17.5 molybdenum, up to 3 iron, up to 1.5 manganese, up to 0.5 aluminum, up to 0.02 carbon, up to 0.015 boron, up to 0.5 silicon, up to 1.5 tungsten and up to 0.5 of each of hafnium, tantalum and zirconium, with a balance of nickel and impurities. Certain alloying elements must be present in amounts according to an equation here disclosed.

Age-hardenable, corrosion resistant Ni&#x2014;Cr&#x2014;Mo alloys

A single step heat treatment for Ni-Cr-Mo alloys containing from 12% to 19% chromium and from 18% to 23% molybdenum provides higher yield strength, high tensile strength and other mechanical properties comparable to those observed in similar alloys age-hardened according to current practices. This treatment is done over a total time of at least 24 hours and preferably less than 50 hours. However, the treatment works for only those alloys having alloying elements present in amounts according to an equation here disclosed.

Aging treatment for Ni-Cr-Mo alloys

A two step heat treatment for Ni&mdash;Cr&mdash;Mo alloys containing from 12% to 23.5% chromium provides higher yield strength, high tensile strength and other mechanical properties comparable to those observed in similar alloys age-hardened according to current practices. This treatment is done over a total time of not more than 50 hours. However, the treatment works for only those alloys having alloying elements present in amounts according to an equation here disclosed.

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Kokomo, IN, United States of America

Lee M Pike, Jr