Estudo investigativo da influência das taxas de solidificação nas ligas de alumínio A380.0 e A359.0: microestruturas e propriedades mecânicas resultantes

Abstract

This undergraduate thesis aimed to investigate the influence of solidification rates on the microstructural characteristics and mechanical properties of A380.0 and A359.0 aluminum alloys, which are crucial in determining the performance and applicability of these materials in various industrial contexts. Through a methodological approach that encompassed a detailed bibliographic analysis, both qualitative and quantitative, and comparative studies, it was possible to elucidate how variations in solidification rates significantly affect the formation of the microstructure and, consequently, the mechanical properties of the alloys under study. The findings demonstrated that faster solidification rates promote the formation of more refined microstructures, which translates into improvements in mechanical properties, such as increased tensile strength and hardness. This phenomenon is attributed to the narrower secondary dendritic arm spacing (SDAS) observed in alloys that underwent accelerated solidification processes. Moreover, a distinction was made between the A380.0 alloy, of secondary nature and obtained through the recycling of aluminum scrap, and the A359.0 alloy, of primary nature and produced from aluminum extracted by bauxite beneficiation, highlighting the relevance of origin and composition in defining the final properties of the materials. This study significantly contributes to the enrichment of scientific literature in Portuguese on the subject, expanding the understanding of the importance of solidification rates in the development of aluminum alloys with optimized mechanical properties and microstructures. The findings reinforce the need to consider the solidification rate as a crucial parameter in the manufacturing process and thermal treatment of aluminum alloys, aiming at obtaining materials with superior characteristics for specific industrial applications.