Estudo das propriedades da liga de alumínio 7075 termicamente tratada

Abstract

Aluminum is the second most produced metal today, as shown by the International Aluminum Institute. Its use increases every year in various industrial sectors, such as naval, aerospace, and automotive industries. The properties of aluminum alloys, such as high strength and low density, are key factors that explain the increased use of this material. The 7075 aluminum alloy belongs to the 7xxx family and is classified as heat treatable, meaning that heat treatments are applied to improve its properties. However, these are costly processes, so understanding the behavior of alloys during this stage and controlling the treatment parameters is crucial for optimizing the process and making it more efficient. In the present study, through metallographic analysis and hardness tests on specimens, the influence of heat treatments on the microstructure and hardness properties of 7075 aluminum was evaluated. During the treatments, the metal proved to be extremely sensitive to temperature changes and the duration of exposure to this increased energy. Metallographic tests revealed significant changes in the microstructure of each sample due to variations in these factors in each treatment, which were designated as sample 1 (original T651 state), sample 2 (annealed state), and sample 3 for the T6 treatment. The samples with T6 treatments showed the highest hardness values, accompanied by a finely dispersed microstructure, while sample 2 successfully removed the mechanical properties of the previous treatment of the original sample. Through these treatments, the influence of the parameters used was successfully verified.