Ati Properties, Inc.

United Technologies Corporation

Teledyne Industries, Inc.

Laurence A Jackman

A Stewart Ballantyne

Betsy J Bond

Daniel F Paulonis

Paul D Genereux

John A Miller

Jeffery W Samuelson

William M Thomas

Frederick P Vaccaro

A method of producing a nickel base alloy includes casting the alloy within a casting mold and subsequently annealing and overaging the ingot at at least 1200&deg; F. (649&deg; C.) for at least 10 hours. The ingot is electroslag remelted at a melt rate of at least 8 lbs/min. (3.63 kg/min.), and the ESR ingot is then transferred to a heating furnace within 4 hours of complete solidification and is subjected to a novel post-ESR heat treatment. A suitable VAR electrode is provided form the ESR ingot, and the electrode is vacuum arc remelted at a melt rate of 8 to 11 lbs/minute (3.63 to 5.00 kg/minute) to provide a VAR ingot. The method allows premium quality VAR ingots having diameters greater than 30 inches (762 mm) to be prepared from Alloy 718 and other nickel base superalloys subject to significant segregation on casting.

Large diameter ingots of nickel base alloys

A method of producing a nickel base alloy includes casting the alloy within a casting mold and subsequently annealing and overaging the ingot at at least 1200&deg; F. (649&deg; C.) for at least 10 hours. The ingot is electroslag remeelted at a melt rate of at least 8 lbs/min (3.63 kg/mm.), and the ESR ingot is then transferred to a heating furnace within 4 hours of complete solidification and is subjected to a novel post-ESR heat treatment. A suitable VAR electrode is provided form the ESR ingot, and the electrode is vacuum arc remelted at a melt rate of 8 to 11 lbs/minute (3.63 to 5.00 kg/minute) to provide a VAR ingot. The method allows premium quality VAR ingots having diameters greater than 30 inches (762 mm) to be prepared from Alloy and other nickel base superalloys subject to significant segregation on casting.

Method for producing large diameter ingots of nickel base alloys

A process for producing a fine grain forged superalloy article having a high yield strength at intermediate temperatures. A preferred starting composition comprises, by weight, 15% Cr, 13.6% Co, 4.1% Mo, 4.6% Ti, 2.2% Al, 0.01% C, 0.007% B, 0.07% Zr, balance Ni. This material is forged at a temperature above the gamma prime solvus and at a true strain of at least 0.5. Alternately, the material may be forged below the gamma prime solvus temperature with intermediate super solvus anneals. The overaged material is then worked at a temperature below the gamma prime solvus. The resultant fine grain material is then heat treated or can be further isothermally forged prior to heat treatment to produce complex shapes.

Superalloy forging process

Growing community of inventors

Monroe, NC, United States of America

Laurence A Jackman