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