The Effect of Quench Delay on Structure and Corrosion Properties of Aluminum Lithium Alloy 2091

Abstract

The aerospace industry is always trying to improve aircraft performance and reduce aircraft weight. Therefore aluminum lithium alloys are targeted as advanced materials for aerospace technology because of their low density, good corrosion resistance, high toughness and lightweight. This 2091 alloy is an aluminum-lithium alloy which has a composition 2.1 wt% Cu, 2.0 wt% Li dan 0.1 wt% Zr. This alloy has been subjected to quench delay heat treatment to enhance corrosion resistance. The experiments were carried out to determine the relationship between delay quenching and its corrosion properties. Aluminum-lithium 2091 had solutionized at 525°C for 6 hours and then has been quenched in water with a variation of delay quenching (30 second, 60 second, 90 second). Characterization using x-ray diffraction were used to investigate the phase of each sample. The results show different diffraction patterns from one sample to another due to delay quenching. While electrochemical testing using a 3.5% NaCl solution show different corrosion resistance due different quench delay.