Experimental Investigation of Deformation in 5083 Marine-Grade Aluminum Alloy at Elevated Temperatures

This paper presents an experimental study to investigate the thermo-mechanical behavior of marine-grade aluminum alloy (AA5083) under quasi-static loading. A series of tensile tests were conducted to generate the true stress-true strain curves at a range of initial temperatures between 25 and 350 °C and at low to intermediate strain rates of 0.001 and 0.1 s⁻¹; respectively. The coupling effect of temperature and strain rate on the flow stress of AA5083 was more pronounced at elevated temperatures. Microhardness tests were also conducted at 1 cm intervals along the gage length. Consistent relationships between the fracture strength of the specimens and their microhardness profiles were observed. Scanning electron microscopy (SEM) coupled with image analysis techniques was used to characterize the internal damage at fracture. The size and area of void growth and coalescence were obtained and SEM results showed that void fraction increases with temperatures and accumulation of plastic strain.