Experimental Investigation of Mechanical Properties of Aluminum Alloy at High and Low Temperatures

Aluminum alloys are increasingly applied in spatial structures owing to their light weight and favorable ductility. The study on mechanical properties at different temperatures is of significance in studying the behavior of aluminum alloy structures under extreme conditions. In this study, tensile tests on certain brands of aluminum alloys commonly used in spatial structures were performed at temperatures ranged from −100°C to 300°C. The elastic modulus, ultimate strength, nominal yield strength, and elongation of the specimens were obtained. It was revealed that aluminum alloys perform improvement in both strength and ductility at low temperatures, and the mechanical properties of aluminum alloys drop rapidly at high temperatures. Subsequently, the constitutive relationship of aluminum alloys at different temperatures was investigated. Moreover, fracture analysis carried out through scanning electron microscope (SEM) indicated different microscopic mechanisms at extreme temperatures. Finally, the temperature influence factor for mechanical properties, which are necessary in spatial structure design, were proposed.