Efeito do SiC na microestrutura e propriedades de rolos cerâmicos de Al2O3/mulita.

Abstract

This dissertation discusses the effect of the addition of silicon carbide (SiC) on the microstructure and properties of Al2O3/mullite ceramic rolls obtained by the extrusion process. The purpose of adding SiC was to render the material more heat-resistant without affecting its mechanical properties, thereby increasing the range of the end product s industrial applications. The starting materials used here were the commercial powders used by Refratários Paulista Indústria e Comércio Ltda in its production of Al2O3/mullite ceramic rolls, and the addition of SiC resulted in Al2O3/mullite/SiC products with higher thermal shock resistance, and greater mechanical strength and heat resistance. The consistency of the mass and the extrusion samples were carefully controlled to maintain the characteristics of constant flow. The processed samples were structurally characterized by scanning electron microscopy and X-ray diffraction to determine their thermal expansion coefficient, apparent density and porosity, flexural strength, and resistance to thermal shock. The industrial performance of Al2O3/mullite/SiC ceramic rolls and their thermal shock resistance were compared with samples of Al2O3/mullite ceramic rolls.