Improvement of the Mechanical Properties of Glasses based on the 3CaO center dot P2O5-SiO2-MgO System after Heat-Treatment

Autor(es)

Daguano, J. K. M. F. ; Santos, C. ; Suzuki, P. A. ; Bicalho, L. A. ; Fernandes, M. H. F. V. ; Rosa, LG ; Margarido, F

• Tipo de documento: Artigo Científico
• Fonte: Materials Science Forum; v. 636-637, p. 2-pg., 2010-01-01.

Resumo

Glasses based on the 3CaO center dot P2O5-SiO2-MgO system present high bioactivity aiming the use as bone restorations. On the other hand, the low mechanical properties reduce the importance of this glass aiming the use as restoration bulk specimens. In this work, glass-ceramics were obtained by devitrification of this glass using different temperatures. CaCO3, SiO2, MgO and Ca(H2PO4)center dot H2O were used as starting-powders. Powder mixture was milled/homogenized and melted at 1600 degrees C, for 2h and annealed at 700 degrees C for 4h with cooling rate of 3 degrees C/min. Glass specimens of 15x15x50mm(3) were characterized by DTA and XRD analysis. Specimens were heat-treated in different temperatures between 700 degrees C and 1050 degrees C, for 4 hours, obtaining glass-ceramics with different crystallized phase content. Hardness and fracture toughness were determined and correlated with crystalline phase content. The results indicated that crystallization-degree increase with the temperature, and the mechanical properties are improved: Hardness values present increases lower than 20% as function of the crystallization. Fracture toughness may increase 100% as function of temperature (crystallization degree). (AU)

• Processo FAPESP: 04/04386-1 - Desenvolvimento e caracterização de pilares cerâmicos biocompatíveis à base de compósitos Zr02-Al2O3
• Beneficiário: Claudinei dos Santos
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 07/50681-3 - Efeito da cristalizacao parcial nas propriedades mecanicas de vitroceramicos bioativos do sistema 3cao.p2o5-sio2-mgo.
• Beneficiário: Marcela Rego de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 07/50510-4 - Efeito da cristalização parcial de vitrocerâmicos bioativos do sistema 3CaO.P2O5-SiO2-MgO nas propriedades mecânicas e biológicas
• Beneficiário: Juliana Kelmy Macário Barboza Daguano
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto