High Strength and Wear Resistant Aluminum Alloy Extrusion Producing Uniform Anodic Film in Thickness and Process for Manufacturing the Same

摘要

This aluminum alloy extrusion has a composition which consists of 6-12 percent Si, 0.1-1.0 percent Fe, 1.0-5.0 percent Cu, 0.1-1.0 percent Mn, 0.4-2.0 percent Mg, 0.01-0.3 percent Ti, 0.005-0.2 percent Sr, and the balance Al with impurities and in which the content of Ni as an impurity is limited to <0.05 percent. In this case, the mean grain size of eutectic Si grains dispersed in matrix is regulated to 1.5-5.0 mu m, and the number of eutectic Si grains is present by 5000 to 10000 pieces/mm~2. This high strength alloy with good wear resistibility and uniform thickness of anodic film is particularly suitable for compressor parts for air-conditioning equipment, such as piston and scroll.