Abstract: An aluminum alloy article containing the alloying amounts of iron, silicon, manganese, titanium, and zinc has controlled levels of iron and manganese to produce an alloy article that combines excellent corrosion resistant with good formability. The alloy article composition employs a controlled ratio of manganese to iron and controlled total amounts of iron and manganese to form intermetallic compounds in the final alloy article. The electrolytic potential of the intermetallic compounds match the aluminum matrix of the article to minimize corrosion. The levels of iron and manganese are controlled so that the intermetallic compounds are present in a volume fraction that allows the alloy article to be easily formed. The aluminum alloy composition is especially adapted for extrusion processes, and tubing that are used in heat exchanger applications.

Abstract: An aluminum alloy composition includes controlled amounts of iron, manganese, zinc, zirconium, vanadium, and titanium to effectively inhibit grain growth during exposure to elevated temperatures while maintaining extrudability and corrosion resistance. The composition is especially adapted for use as micro-multivoid tubing for brazed heat exchanger applications and has a post-braze grain structure that is more resistant to intergranular corrosion so as to reduce or eliminate heat exchanger failures during service.

Abstract: An aluminum alloy article containing the alloying amounts of iron, silicon, manganese, titanium, and zinc has controlled levels of iron and manganese to produce an alloy article that combines excellent corrosion resistant with good formability. The alloy article composition employs a controlled ratio of manganese to iron and controlled total amounts of iron and manganese to form intermetallic compounds in the final alloy article. The electrolytic potential of the intermetallic compounds match the aluminum matrix of the article to minimize corrosion. The levels of iron and manganese are controlled so that the intermetallic compounds are present in a volume fraction that allows the alloy article to be easily formed. The aluminum alloy composition is especially adapted for extrusion processes, and tubing that are used in heat exchanger applications.

Abstract: An aluminum-based alloy composition having improved combinations of strength and fracture toughness consists essentially of 2.5-5.5 percent copper, 0.10-2.30 percent magnesium, with minor amounts of grain refining elements, dispersoid additions and impurities and the balance aluminum. The amounts of copper and magnesium are controlled such that the solid solubility limit for these elements in aluminum is not exceeded. The inventive alloy composition may also include 0.10-1.00 percent silver for improved mechanical properties. The alloys are useful as high strength, high fracture toughness components for aircraft and aerospace structural parts.

Abstract: A process for producing an aluminum-based alloy composition having improved combinations of strength and fracture toughness. The process includes casting an ingot consisting essentially of 2.5-5.5 percent copper, 0.10-2.30 percent magnesium, with minor amounts of grain refining elements, dispersoid additions and impurities and the balance aluminum. The amounts of copper and magnesium are controlled such that the solid solubility limit for these elements in aluminum is not exceeded. The alloy composition also includes 0.10-1.00 percent silver for improved mechanical properties. The ingot, in accordance with the inventive process, is homogenized and worked to produce a product. The product is solution heat treated to obtain a saturated solid solution and then aged to develop an improved combination of high strength and fracture toughness.

Abstract: An aluminum-based alloy composition having improved combinations of strength and fracture toughness consists essentially of 2.5-5.5 percent copper, 0.10-2.30 percent magnesium, with minor amounts of grain refining elements, dispersoid additions and impurities and the balance aluminum. The amounts of copper and magnesium are controlled such that the solid solubility limit for these elements in aluminum is not exceeded. The inventive alloy composition may also include 0.10-1.00 percent silver for improved mechanical properties. The alloys are useful as high strength, high fracture toughness components for aircraft and aerospace structural parts.

Abstract: The present invention provides a method for improving aluminum alloy plate product properties by delaying final stretching of the plate product. During processing of the product, a time interval or intentional delay is provided between the final cold rolling step and the final stretching step. By delaying the final stretching procedure, an aluminum alloy plate product is provided with an improved fracture toughness without significant decrease in strength values. The method of intentionally delaying final stretching is particularly adapted for 2000 series aluminum alloys.

Abstract: High Temperature Oxidation (HTO) of aluminum subjected to heat treatment is controlled by exposing the aluminum surface to a metal chloride prior to heat treatment. Transition metal chlorides are preferred for such treatment.