Abstract: The present invention provides extruded tubes for heat exchangers having improved corrosion resistance when used alone and when part of a brazed heat exchanger assembly with compatible finstock. The tubes are formed from a first aluminum alloy containing 0.4 to 1.1% by weight manganese, up to 0.01% by weight copper, up to 0.05% by weight zinc, up to 0.2% by weight iron, up to 0.2% by weight silicon, up to 0.01% by weight nickel, up to 0.05% by weight titanium and the balance aluminum and incidental impurities. The fins are formed from a second aluminum alloy containing 0.9 to 1.5% by weight manganese or an alloy of the AA3003 type, this second aluminum alloy further containing at least 0.5% by weight zinc.

Abstract: The present invention provides extruded tubes for heat exchangers having improved corrosion resistance when used alone and when part of a brazed heat exchanger assembly with compatible finstock. The tubes are formed from a first aluminum alloy containing 0.4 to 1.1% by weight manganese, up to 0.01% by weight copper, up to 0.05% by weight zinc, up to 0.2% by weight iron, up to 0.2% by weight silicon, up to 0.01% by weight nickel, up to 0.05% by weight titanium and the balance aluminum and incidental impurities. The fins are formed from a second aluminum alloy containing 0.9 to 1.5% by weight manganese or an alloy of the AA3003 type, this second aluminum alloy further containing at least 0.5% by weight zinc.

Abstract: A novel extrudable aluminum based alloy is described consisting essentially of 0.60-0.84% magnesium, 0.45-0.58% silicon, 0.15-0.40% copper, 0.04-0.35% chromium, or 0.20-0.80% manganese, less than 0.25% iron, where Si>=(Mg/1.73+(Mn+Cr+Fe)/3−0.04), and the balance essentially aluminum. In the alloy of the present invention, the magnesium content has been reduced to the minimum possible for mechanical properties. In this way, the magnesium silicide content of the alloy has been reduced, providing a very beneficial effect on extrudability.

Abstract: Aluminum alloy products are described which combine both good strength and resistance to pitting corrosion. They are extruded from an aluminum alloy of the AA1000, AA3000 or AA8000 series containing about 0.001 to 0.3% zinc and about 0.001 to 0.03% titanium. The alloy may also contain 0.001 to 0.5% manganese and about 0.03 to 0.4% silicon. These products are particularly useful in the production of extruded products, such as heat exchanger tubing.