Effect of Re-Aging on Strength, Corrosion and Dry Sliding Wear Behavior of 7075 Aluminum Alloy

Abstract

The effect of re-ageing on hardness, pin-on-disc sliding wear and corrosive behavior of 7075 aluminum alloy is studied. The as cast alloy was solution treated at 470 °C for 2hrs and aged at 120 °C for 6 and 24hrs respectively. Wear tests were conducted on a pin-on-disc- wear testing machine with die steel rotating disc. Corrosion tests were carried out in 3.5% aqueous solution. Ageing at 120 °C for 6hrs improved the wear resistance on increasing speed from 100 - 400 m/sec at a constant load of 5N. The Ageing at 120 °C for 24hrs enhanced the wear property on increasing load from 5 - 15N at constant speed 100 m/sec. Ageing for 24hrs exhibited higher corrosion resistance than the alloy aged for 6hrs and the original alloy. With the help of optical and scanning electron microscopic analysis, the mechanism of wear and corrosion has been predicted. The study may help in developing improved property of the heat-treatable aluminum alloys.