Alcoa Inc.

Aluminum Company of America

Novelis, Inc.

Arconic Corporation

Aloca Inc.

Dhruba J Chakrabarti

Robert W Westerlund

Gregory B Venema

John Liu

Ralph R Sawtell

Jay H Goodman

Cynthia M Krist

Gary H Bray

Paul E Magnusen

Diana K Denzer

Anthony Morales

Jen C Lin

John Newman

Cagatay Yanar

Roger D Doherty

Craig L Jensen

Julien Boselli

Daniel T Moulton

Anne E Zemo

Terrence N Thom

Roberto J Rioja

Rajeev G Kamat

Stephen F Baumann

Juergen Timm

Duane E Bendzinski

Philip E Bretz

Rashmi Ranjan Mohanty

Vivek M Sample

Richard A Hoffman

Rahul Vilas Kulkarni

James T Staley

William D Bennon

Bruce A Halter

Anne E Roberts

Yanar Cagatay

Described herein are novel 7xxx series aluminum alloys. The alloys exhibit high strength. The alloys can be used in a variety of applications, including automotive, transportation, electronics, aerospace, and industrial applications. Also described herein are methods of making and processing the alloys. Further described herein are methods of producing a metal sheet, which include casting an aluminum alloy as described herein to form an ingot, homogenizing the ingot, hot rolling the ingot to produce a hot band, and cold rolling the hot band to a metal sheet of final gauge.

High strength 7xxx aluminum alloys and methods of making the same

Aluminum alloy products, such as plate, forgings and extrusions, suitable for use in making aerospace structural components like integral wing spars, ribs and webs, comprises about: 6 to 10 wt. % Zn; 1.2 to 1.9 wt. % Mg; 1.2 to 2.2 wt. % Cu, with Mg&#x2264;(Cu+0.3); and 0.05 to 0.4 wt. % Zr, the balance Al, incidental elements and impurities. Preferably, the alloy contains about 6.9 to 8.5 wt. % Zn; 1.2 to 1.7 wt. % Mg; 1.3 to 2 wt. % Cu. This alloy provides improved combinations of strength and fracture toughness in thick gauges. When artificially aged per the 3-stage method of preferred embodiments, this alloy also achieves superior SCC performance, including under seacoast conditions.

Aluminum alloy products having improved property combinations and method for artificially aging same

Aluminum alloy products about 4 inches thick or less that possesses the ability to achieve, when solution heat treated, quenched, and artificially aged, and in parts made from the products, an improved combination of strength, fracture toughness and corrosion resistance, the alloy consisting essentially of: about 6.8 to about 8.5 wt. % Zn, about 1.5 to about 2.00 wt. % Mg, about 1.75 to about 2.3 wt. % Cu; about 0.05 to about 0.3 wt. % Zr, less than about 0.1 wt. % Mn, less than about 0.05 wt. % Cr, the balance Al, incidental elements and impurities and a method for making same. The instantly disclosed alloys are useful in making structural members for commercial airplanes including, but not limited to, upper wing skins and stringers, spar caps, spar webs and ribs of either built-up or integral construction.

Aluminum alloy products, such as plate, forgings and extrusions, suitable for use in making aerospace structural components like integral wing spars, ribs and webs, comprises about: 6 to 10 wt. % Zn; 1.2 to 1.9 wt. % Mg; 1.2 to 2.2 wt. % Cu, with Mg&#x2266;(Cu+0.3); and 0.05 to 0.4 wt. % Zr, the balance Al, incidental elements and impurities. Preferably, the alloy contains about 6.9 to 8.5 wt. % Zn; 1.2 to 1.7 wt. % Mg; 1.3 to 2 wt. % Cu. This alloy provides improved combinations of strength and fracture toughness in thick gauges. When artificially aged per the 3-stage method of preferred embodiments, this alloy also achieves superior SCC performance, including under seacoast conditions.

Aluminum alloy products, such as plate, forgings and extrusions, suitable for use in making aerospace structural components like integral wing spars, ribs and webs, comprises about: 6 to 10 wt. % Zn; 1.2 to 1.9 wt. % Mg; 1.2 to 2.2 wt. % Cu, with Mg&#x2266;(Cu+0.3); and 0.05 to 0.4 wt. % Zr, the balance Al, incidental elements and impurities. Preferably, the alloy contains about 6.9 to 8.5 wt. % Zn; 1.2 to 1.7 wt. % Mg; 1.3 to 2 wt. % Cu. This alloy provides improved combinations of strength and fracture toughness in thick gauges. When artificially aged per the three stage method of preferred embodiments, this alloy also achieves superior SCC performance, including under seacoast conditions.

A method of artificially aging an aluminum alloy product to achieve a property in the product having the steps of aging the product to achieve the property by heating the product over an aging period, the aging period including a time period where the product is in an underaged state, and terminating the heating when the property is achieved according to a mathematical formula. The property is calculated as a function of time and product temperature measured over the aging period. Calculation of the property includes integration of the thermal effects on the product over the entire aging period including during the time period of underaged product state.

Artificial aging control of aluminum alloys

A process for improving 6XXX alloys, such as 6013, preferably includes heating, hot rolling, inter-rolling thermal treatment at a very high temperature such as 1020&#xb0; F. or more, again hot rolling (with or without subsequent continuous hot rolling or cold rolling or both), solution heat treating and artificial aging. The initial heating, inter-rolling, thermal treatment and solution treatment, especially the latter two, are carried out at very high temperatures such as 1030&#xb0; F. Each aforesaid hot rolling stage produces substantial metal thickness reduction. The improved sheet or plate product has a substantially reduced occurrence of reduced density features revealed in scanning electron microscope examination at 500X and exhibits improved (reduced) fatigue crack growth rate providing an advantage in aerospace applications such as fuselage skin, especially fuselage belly skin.

Process to improve 6XXX alloys by reducing altered density sites

A process for improving 6XXX alloys, such as 6013, preferably includes heating, hot rolling, inter-rolling thermal treatment at a very high temperature such as 1020&deg; F. or more, again hot rolling (with or without subsequent continuous hot rolling or cold rolling or both), solution heat treating and artificial aging. The initial heating, inter-rolling, thermal treatment and solution treatment, especially the latter two, are carried out at very high temperatures such as 1030&deg; F. Each aforesaid hot rolling stage produces substantial metal thickness reduction. The improved sheet or plate product has a substantially reduced occurrence of reduced density features revealed in scanning electron microscope examination at 500&times; and exhibits improved (reduced) fatigue crack growth rate providing an advantage in aerospace applications such as fuselage skin, especially fuselage belly skin.

The present invention is directed to highly controlled alloy composition relationship of a high purity Al&mdash;Mg&mdash;Cu alloy within the 2000 series aluminum alloys as defined by the Aluminum Association, wherein significant improvements are revealed in fracture toughness through plane strain, fracture toughness through plane stress, fatigue life, and fatigue crack growth resistance.

High toughness plate alloy for aerospace applications

Aluminum sheet products having highly anisotropic grain microstructures and highly textured crystallographic microstructures are disclosed. The products exhibit improved strength and improved resistance to fatigue crack growth, as well as other advantageous properties such as improved combinations of strength and fracture toughness. The sheet products are useful for aerospace and other applications, particularly aircraft fuselages.

Aluminum sheet products having improved fatigue crack growth resistance and methods of making same

A method for making a superplastically formable, aluminum alloy product which consists essentially of: about 2-3.8 wt. % magnesium; at least one dispersoid-forming element selected from the group consisting of: up to about 1.6 wt. % manganese, up to about 0.2 wt. % zirconium, and up to about 0.3 w. % chromium; at least one nucleation-enhancing element for recrystallization selected from: about 0.11-1.0 wt. % silicon, up to about 1.5 wt. % copper, and combinations thereof. Said alloy product has greater than about 300% elongation at a strain rate of about 0.0001-0.003/sec and a superplastic forming temperature between about 1000-1100&deg; F. due, in part to the preferred thermomechanical processing steps applied to its intermediate plate or slab product forms.

Method for making a superplastically-formable AL-Mg product

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Woodside, NY, United States of America

Dhruba J Chakrabarti