Obtenção de compósitos superficiais em matriz de alumínio através do processo de fricção agitação (FSP)

Abstract

Aluminum alloys are currently in high demand in the automotive industry and other industrial sectors. However, improvements are being sought in the wear performance and properties of these aluminum alloys and in this sense the use of metal matrix composites (AMCs) has been an increasingly accepted proposal. Within the processes for obtaining AMCs, the method of processing by friction agitation (FSP), which manages to create a localized superficial AMC, is considered a viable technological solution due to its energetic and metallurgical advantages. This work aims to develop a surface composite by FSP in aluminum alloy A6082 with the addition of reinforcements, being silicon carbide (SiC) and niobium carbide (NbC), both carried out through the deposition by thermal spraying of a layer of controlled thickness of the reinforcement materials used and different amounts of passes in the FSP process were evaluated. The characterization of the samples was performed by optical microscopy, scanning electron microscopy (SEM) and x-ray spectroscopy (EDS). Both Vickers micro hardness tests and scratching tests were performed to determine the coefficient of friction (CoF). There was a reduction in the friction coefficient of the AMCs obtained on the surfaces in relation to the base material, as well as a microstructural improvement in the modified regions through the formation of finer grains. Therefore, the feasibility of the FSP technique for improving the resistance to wear by friction of the A6082 alloy was obtained.