Mechanical and thermal properties of hot pressedCoCrMo–porcelain composites developed forprosthetic dentistry

• Autor(a) principal: Henriques, B.
• Data de Publicação: 2014
• Outros Autores: Gasik, M., Souza, J.C.M., Nascimento, Rubens Maribondo do, Soares, D., Silva, F.S.
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/jspui/handle/123456789/28562
• topic: CoCrMo alloy; Porcelain; Composite; Powder metallurgy; Mechanical properties; Thermal properties

In this study, mechanical and thermal properties of CoCrMo–porcelain composites fordental restorations have been evaluated. These metal–ceramic composites were producedby powder metallurgy and hot pressing techniques from the mixtures of metal and ceramicpowders with different volume fractions. Young's moduli and the coefficient of thermalexpansion of materials were evaluated by dynamic mechanical analysis (DMA) anddilatometry (DIL) tests, respectively. The strength inflexion and shear was measured witha universal test machine and hardness with a respective tester. The microstructures andfracture surfaces were inspected by the means of optical microscopy and ScanningElectron Microscopy/Energy Dispersive Spectroscopy (SEM/EDS).Shear strength, Flexural strength and Young' moduli of ceramic and metal-matrixcomposites were found to increase with higher metal particles content. The DMA testsperformed at different frequencies showed no frequency-dependent features of thematerials studied, indicating no viscoelastic behavior. The fracture surfaces analysissuggests the load-transfer mechanism be possibly responsible for this behavior, as thedifferences in CTE are low enough to cause significant thermal stresses in these materials.The results might be included in a materials properties database for further use for designand optimization of dental restorations.