Efeito do niobato de alumínio (AINbO4) como aditivo na sinterização convencional e flash de compósitos alumina/zircônia

Abstract

Alumina is a ceramic material widely used in many applications that require high mechanical strength. Allied to this, it is a low cost material when compared to other advanced ceramics. What limits its use in some applications is its fragility, so there was a need to create a new range of materials, the composites. They are capable of bringing together different useful properties in the same material. A possible combination that tends to reduce alumina brittleness is its admixture with zirconia, a material that has a change in structure that provides increased fracture toughness of alumina. This paper aims to analyze two composite formulation: one widely known in the market, composed of alumina and zirconia and another containing alumina, zirconia and aluminium niobate. Aluminium niobate has the function of acting as a liquid phase former in the sintering process, thus reducing energy consumpiton to produce the same densification, making it possible to cheapen the product. In this study, it was possible to analyze the possibility of producting these materials by flash sintering and their influence on the composite microstructure. It was observed that with 1% additive it was possible to produce the samples by flash sintering. It was possible to obtain an increase in hardness and density of the composites produced by conventional sintering.