Structural members having improved resistance to fatigue crack growth
AssigneeAlcoa Inc.
InventorsMatthew D. Garratt, Gary H. Bray, Diana K. Denzer, Patrick Ulysse
Life of this patent
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Abstract
An extruded structural member having improved damage tolerance containing a base section (6); a stiffening section having at least one pair of structural stiffeners (10), the structural stiffeners integral with the base section (6) and projecting outwardly thereof; and at least one intra-stiffener (90) area positioned between the pair of structural stiffeners (10), the intra-stiffener area (90) having a microstructure with intentionally increased amounts of fiber texture to reduce the rate of fatigue crack growth in the extruded structural member.
Claims33
An extruded structural member having improved damage tolerance, said structural member comprising:
- at least one area having a substantially unrecrystallized microstructure with intentionally increased amounts of fiber texture of at least one area to reduce the rate of fatigue crack growth in said extruded structural member
- wherein said intentionally increased fiber texture of said least one area is formed by intentionally extruded local geometries which promote primarily axisymmetric metal flow and then removing excess metal in said local geometries.
An extruded structural member having improved damage tolerance, said structural member comprising:
- a base section;
- a stiffening section having at least one pair of structural stiffeners, said structural stiffeners are integral with said base section and projecting outwardly thereof;
- and
- at least one intra-stiffener area positioned between said pair of structural stiffeners, said intra-stiffener area having a microstructure with intentionally increased amounts of fiber texture to reduce the rate of fatigue crack growth in said extruded structural member wherein said intentionally increased fiber texture of said least one intra stiffener area is formed by intentionally extruded local geometries which promote primarily axisymmetric metal flow and then removing excess metal in said local geometries.
Dependencies are inferred from the claim text.