Implementation of the SEVNB method to measure the fracture toughness of liquid phase sintered SiC ceramics using Al2O3-Yb2O3 or Al2O3-Nd2O3 as additives

• Grant number: 10/51925-6
• Support Opportunities: Regular Research Grants
• Start date: December 01, 2010
• End date: May 31, 2013
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Sebastião Ribeiro
• Grantee: Sebastião Ribeiro
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil

Abstract

Silicon carbide-based ceramics, SiC, are widely applied in engineering due to their excellent mechanical, thermal and chemical properties. To produce SiC ceramics with specific properties for each application requires selecting the processing method that will result in suitable micro structures. Therefore, these ceramics are normally sintered via liquid phase, using mixtures of aluminum and rare earth oxides, e.g., Al2O3/Y2O3, Al2O3/Sm2O3, Al2O3/E2O3 (E2O3 is a rare earth oxide mixture from xenotime) and Al2O3/La2O3 as liquid-phase formers. Fracture toughness, K1C, is an important mechanical property that often restricts ceramic applications. The measurement of K1C is a controversial issue, both from the standpoint of the methods employed and the mathematical equations used in determining this property. Another important property of advanced ceramics that is often neglected but which is widely known in the area of refractories is the energy of fracture, which allows one to evaluate the thermal shock resistance of ceramics used in applications in which this phenomenon is present. This project has two main and equally important objectives, namely: 1) Implement the SEVNB method to measure K1C at DEMAR/EEL/USP, which, albeit widely used abroad and offering numerous advantages compared with other methods, is very little known and used in Brazil. 2) Introduce two more rare earth oxides as liquid phase formers in SiC sintering, taking advantage of our previous experience with other rare earth oxides. In addition to training human resources. (AU)

Scientific publications

(7)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RIBEIRO, SEBASTIAO; RIBEIRO, GISELI CRISTINA; DE OLIVEIRA, MARCELA REGO. Properties of SiC Ceramics Sintered via Liquid Phase Using Al2O3 + Y2O3, Al2O3 + Yb2O3 and Al2O3 + Dy2O3 as Additives: a Comparative Study. MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS, v. 18, n. 3, p. 525-529, MAY-JUN 2015. (10/51925-6)

S. RIBEIRO; G. C. RIBEIRO; J. A. RODRIGUES. Tenacidade à fratura de cerâmicas de carbeto de silício, alumina e argila vermelha pelos métodos IF e SEVNB. Cerâmica, v. 60, n. 356, p. 509-515, 2014-12-00. (10/51925-6)

DA SILVA, J. A.; MORESCHI, B. M.; GARCIA, G. C. R.; RIBEIRO, S.. Wettability of silicon carbide ceramic by Al2O3/Dy2O3 and Al2O3/Yb2O3 systems. JOURNAL OF RARE EARTHS, v. 31, n. 6, p. 634-638, JUN 2013. (10/51925-6, 12/01665-3, 12/01177-9)

RIBEIRO, S.; GENOVA, L. A.; RIBEIRO, G. C.; OLIVEIRA, M. R.; BRESSIANI, A. H. A.. Effect of temperature and heating rate on the sintering performance of SiC-Al2O3-Dy2O3 and SiC-Al2O3-Yb2O3 systems. CERAMICS INTERNATIONAL, v. 43, n. 18, p. 16048-16054, DEC 15 2017. (13/08032-9, 10/51925-6)

S. RIBEIRO; I. ATÍLIO; M. R. OLIVEIRA; G. C. R. GARCIA; J. A. RODRIGUES. Entalhamento de cerâmicas para medida de tenacidade à fratura pelo método SEVNB. Cerâmica, v. 59, n. 350, p. 285-292, 2013-06-00. (10/51925-6)

RIBEIRO, S.; GENOVA, L. A.; RIBEIRO, G. C.; OLIVEIRA, M. R.; BRESSIANI, A. H. A.. Effect of heating rate on the shrinkage and microstructure of liquid phase sintered SiC ceramics. CERAMICS INTERNATIONAL, v. 42, n. 15, p. 17398-17404, NOV 15 2016. (13/08032-9, 10/51925-6)

RIBEIRO, SEBASTIAO; RIBEIRO, GISELI CRISTINA; DE OLIVEIRA, MARCELA REGO. Properties of SiC Ceramics Sintered via Liquid Phase Using Al2O3 + Y2O3, Al2O3 + Yb2O3 and Al2O3 + Dy2O3 as Additives: a Comparative Study. MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS, v. 18, n. 3, p. 5-pg., 2015-05-01. (10/51925-6)