Cabot Corporation

Haynes International, Inc.

Other

Robert B Herchenroeder

George Y Lai

William L Silence

Russell W Kirchner

H Joseph Klein

Dennis S Acuncius

Coleman M Augustine, Jr

Boyd A Heath

Christopher R Patriarca

Dennis A Acuncius

Krishna V Rao

An inert gas nitrogen mixture is used as a shielding gas to prevent weld hot cracking in superalloys containing zirconium and/or boron. The gas mixture preferably contains argon and about 2 to 8% by volume nitrogen. Test data show excellent results are obtained when gas tungsten arc welding HAYNES 214 alloy which normally contains boron and zirconium and a minimal content of titanium.

Shielding gas to reduce weld hot cracking

A strand annealing furnace is provided with a tube assembly to shield or protect the strand being annealed from the hot furnace atmosphere. The tube assembly includes a long, outer, oxidation-resistant pipe and a shorter, inner easily removable, insert, protecting at least the entrance end of the tube, so that any residue from drawing lubricants will deposit within the insert rather than block and/or corrode the pipe.

Sacrifical insert for strand annealing furnace tubes

Disclosed is a process for treating the surface of super alloys, notably nickel-base alloys, with thin cross sections, in preparation for brazing processes. The super alloy is heat treated in a partial pressure of oxygen at a temperature less than about 1975.degree. F. but above the engineering solvus temperature of gamma prime intermetallics followed by a rapid cooling step. The resultant alloy is thereby provided with a surface that has improved brazability.

Method of manufacturing brazable super alloys

A yttrium-free, nickel-chromium-iron-aluminum alloy characterized by excellent oxidation resistance at very high temperatures. The alloy consists essentially of, by weight, from 14 to 18% chromium, from 4 to 6% aluminum, from 1.5 to 8% iron, up to 12% cobalt, up to 1% manganese, up to 1% molybdenum, up to 1% silicon, up to 0.25% carbon, up to 0.03% boron, up to 1% tungsten, up to 0.5% tantalum, up to 0.2% titanium, up to 0.5% hafnium, up to 0.2% zirconium, up to 0.2% rhenium, balance essentially nickel. The nickel plus the cobalt content is at least 66%.

Nickel-chromium-iron-aluminum alloy

A high temperature oxidation resistant alloy. The alloy consists essentially of, by weight, from 14 to 18% chromium, from 4 to 6% aluminum, from 1.5 to 8% iron, a small but effective yttrium content not exceeding 0.04%, up to 12% cobalt, up to 1% manganese, up to 1% molybdenum, up to 1% silicon, up to 0.25% carbon, up to 0.03% boron, up to 1% tungsten, up to 1% tantalum, up to 0.5% titanium, up to 0.5% hafnium, up to 0.5% rhenium, up to 0.04% of elements from the group consisting of elements 57 through 71 of the periodic table of the elements, balance essentially nickel. The nickel plus the cobalt content is at least 66%. The iron content is in accordance with the relationship, Fe .gtoreq.3+4 (%Al-5), when the aluminum content is at least 5%.

Iron-bearing nickel-chromium-aluminum-yttrium alloy

An electroslag remelting process for manganese-base alloys. The process includes the steps of: partially immersing a consumable electrode of a manganese-base alloy in a layer of molten slag and passing current between the consumable electrode and a second electrode. The current is passed through the slag layer under conditions which gradually melt the consumable electrode so that drops of molten metal from the consumable electrode move downwardly through the slag layer and resolidify as an ingot thereunder. The slag is characterized by a fusion temperature of more than 300.degree. F. (149.degree. C.), and often more than 350.degree. F. (177.degree. C.), above the melting point of the consumable electrode. It is preferably comprised of Al.sub.2 O.sub.3, CaO and CaF.sub.2.

Process for electroslag remelting of manganese-base alloys

This invention relates to components of ceramic kiln and furnace hardware made of NICRALY alloys. Disclosed is a method of heat treating NICRALY alloys to obtain a uniform film of desired alumina (Al.sub.2 O.sub.3) on the surface of the alloys. The gist of the invention resides in the control of the critical relationship between the temperature and the partial pressure of oxygen in the oxygen potential controlled atmosphere during the heat treatment. Optimum results are obtained when the temperature is about 2100.degree. F. and the dew point is about -30.degree. F. in hydrogen for about one hour.

Method of heat treating NICRALY alloys for use as ceramic kiln and

Disclosed is a NICRALY alloy containing nominally about 16% chromium, about 5.3% aluminum, about 0.02% yttrium and the balance essentially nickel, and heat treated in a manner to develop an essentially aluminum oxide surface. The NICRALY alloy is especially suited for use as components and support systems in kilns that are used in the firing steps in the manufacture of ceramic articles.

Method of heat treating nickel-base alloys for use as ceramic kiln

An improved oxidation resistant iron base alloy article for welding to another article to form a composite product with reduced heat affected zone cracking is provided consisting essentially of about 0.05 to 0.7% carbon, less than 0.3% columbium, about 15 to 30% cobalt, about 18 to 25% chromium, about 0 to 2% manganese, about 1 to 6% molybdenum, about 0.10 to 0.30% nitrogen, about 15 to 30% nickel, about 0.2 to 0.6% silicon, about 0.1 to 2% tantalum, about 1 to 10% tungsten, about 0 to 0.1% zirconium, about 0 to 0.5% aluminum, about 0 to 0.1% lanthanum and the balance iron &gt;23 w/o with incidental impurities not exceeding 0.6% in aggregate. The combined % of columbium and tantalum being at least 0.4% and the combined carbon and nitrogen being &gt;0.2%.

Oxidation resistant iron base alloy articles for welding

Alloys containing 15-29% chromium, 12-35% iron and the balance 38-72% nickel plus cobalt as the essential major ingredients are greatly stabilized with respect to both weld crack resistance and oxidation resistance by the addition of lanthanum in effective but carefully controlled amounts of less than 0.10% and preferably less than 0.08% in the presence of between about 0.2 and 2.0% silicon as an essential minor ingredient.

Weldable alloys

An alloy containing 20-23% chromium, 17-20% iron, up to 2.5% cobalt, 7-10% molybdenum, up to 1% tungsten, up to 0.15% carbon, 0.2-1% silicon, up to 1% manganese and the balance nickel is greatly stabilized with respect to weld crack resistance by the addition of lanthanum in effective but small carefully controlled amounts to 0.08% in the presence of silicon as an essential minor ingredient.

Weldable alloy

A thermally stable, oxidation-resistant nickel-base alloy having good engineering properties for use in mechanical equipment operated at temperatures of up to 1600.degree. F. or higher is provided by maintaining the nickel content above 50% by weight and including as essential elements from about 12 to about 18% chromium, from about 8 to about 18% molybdenum and from about 0.005 to about 0.2% lanthanum by weight. Additional elements may be included in limited amounts provided that the average N.sub.v number of the alloy as defined herein is not substantially above about 2.5 and preferably is below about 2.4.

Thermally stable high-temperature nickel-base alloys

A cast thermally stable high temperature nickel-base alloy characterized by superior oxidation resistance, sustainable hot strength and retention of ductility on aging is provided by maintaining the alloy chemistry within the composition molybdenum 13.7% to 15.5%; chromium 14.7% to 16.5%; carbon up to 0.1%, lanthanum in an effective amount to provide oxidation resistance up to 0.08%; boron up to 0.015%; manganese 0.3% to 1.0%; silicon 0.2% to 0.8; cobalt up to 2.0%; iron up to 3.0%; tungsten up to 1.0%; copper up to 0.4%; phosphorous up to 0.02%; sulfur up to 0.015%; aluminum 0.1% to 0.5% and the balance nickel while maintaining the Nv number less than 2.31.

Cast thermally stable high temperature nickel-base alloys and casting

A ductile cobalt-base alloy having high strength is provided having molybdenum in the range 1% to 8% molybdenum by weight.

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Kokomo, IN, United States of America

Robert B Herchenroeder