Mechanical properties of high strength aluminium alloy at elevated temperatures

The mechanical properties of extruded aluminium alloys behave differently as temperature rises. Accurate prediction of the mechanical properties of aluminium alloys at elevated temperatures is necessary for determining the load-carrying capacity of structures under fire conditions. This study focuses on the effects of high strength aluminium alloy 6061-T6 at elevated temperatures. The melting point of aluminium alloy 6061-T6 is found to be approximately 650°C. Therefore, tensile coupon tests were conducted at different temperatures ranging from approximately 24 to 600 °C for both steady and transient state tests. The material properties of aluminium alloy 6061-T6 with plate thickness of 4.5 mm were obtained. The tests were performed using servo-controlled hydraulic testing machine equipped with MTS 653 furnace. The Young's modulus, the yield strength (i.e. the 0.2% proof stress) and the ultimate strength versus different temperatures are also plotted and compared with the predictions from the American Aluminum Design Manual and Eurocode EN1999-1-2. The comparisons of the results are plotted and summarized in this paper, together with a detailed discussion. It is found that both the American Aluminum Design Manual and Eurocode generally provide conservative predictions for the high strength aluminium alloys at elevated temperatures.