Avaliação da variação da resistência ao desgaste da liga de alumínio A380 modificada e tratada termicamente em 3 temperaturas diferentes de homogeneização

Abstract

Aluminum is the metal found in most quantity in the Earth's crust, being used for the most diverse purposes in the automotive, food, energy, electronics, transmission, aeronautics and other industries. A good thermal and electrical conductor, it is also recyclable and can be combined with various other materials, forming alloys, so that it can improve its properties and serve a variety of purposes. This study is aboute the modified A380 alloy, which is an Al-Si alloy and also contains the refined 5Ti1B and 5Ti2B, where it was heat treated by homogenization. The objective of this study is to do this heat treatment at temperatures of 470ºC, 500ºC and 530ºC and evaluate the results obtained in relation to hardness and resistance to cavitation wear. To obtain these data, Rockwell hardness, Vickers microhardness, cavitation wear resistance and Scanning Electron Microscope (SEM) tests were performed. It was possible to observe that the homogenization temperatures used, despite those recommended, were not ideal, as it was possible to notice that the heat-treated samples had lower hardness than the untreated ones, where solubilization and redistribution of the durable phases probably did not occur in the correct way. As expected, there is only an increase in grain size. In relation to wear resistance, samples treated at 530ºC showed the best performance, even above standard samples. Among the treated samples, this sample also presented the best Rockwell hardness results, which leads to the idea that it is interesting to perform homogenization at temperatures slightly above this, to check whether the results are more overwhelming.