High Rate Mechanical Characterization of Sensitized 5083-H131 Aluminum Alloy

Abstract

For many years 5000 series aluminum alloys have played an important role in weight reduction of air, land and sea vehicles. However, sensitization of these alloys has been a major concern regarding the performance of aging vehicles. As the aluminum ages, magnesium, supersaturated in the matrix, segregates out to grain and precipitate boundaries as Al₃Mg₂ (β phase). The β phase is more electrochemically active than the solid solution, leading to increased sensitivity to corrosion including stress corrosion cracking and costly repairs or replacement (Lim et al., Corrosion 72:198–220, 2015). Studies have mostly focused on the effectiveness of various methods (grain boundary engineering, stabilization, coatings) in reducing corrosion but very little work has been performed on the high rate mechanical response of sensitized aluminum. This study will try to elucidate the effect of sensitization on the mechanical response of AA5083-H131. Specimens will be conditioned up to 28 days at 100 °C. Tension and compression tests will be performed at various loading rates to examine strength and elongation to failure. Results from this study will correlate mechanical response to corrosion criteria while aiding in the development of new alloys resistant to the effects of sensitization.