Compressive creep behavior of hot-pressed Si3N4–CRE2O3–Al2O3 ceramics

Santos, Claudinei dos; Strecker, Kurt; Barboza, Miguel Ribeiro Justino; Neto, Francisco Piorino; Silva, O.M.M.; Silva, C.R.M. da

doi:10.1016/j.materresbull.2004.04.006

Cited by 6 publications

(3 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…that the principal mechanism of deformation by creep is grain sliding by viscous flow. In recently published works the identification and characterization of the creep mechanisms in these materials have been reported and discussed[12,13]. Furthermore, the creep rates determined are in agreement with literature data of Si 3 N 4 -Y 2 O 3 -Al 2 O 3 or AlN ceramic materials[8][9][10][11][12].…”

supporting

confidence: 80%

“…In recently published works the identification and characterization of the creep mechanisms in these materials have been reported and discussed[12,13]. Furthermore, the creep rates determined are in agreement with literature data of Si 3 N 4 -Y 2 O 3 -Al 2 O 3 or AlN ceramic materials[8][9][10][11][12]. Si 3 N 4 ) were obtained by uniaxial hot-pressing, using a low cost sintering additive produced at FAENQUIL, denominated RE2 O 3 .…”

supporting

confidence: 76%

“…Crystalline phases were determined by XRD and sample's microstructures were observed by SEM. Compressive creep tests were carried out in air, at temperatures ranging from 1250 to 1375 o C and under nominal stresses from 100 to 350 MPa, for up to 60 h. The details of the experimental device can be found elsewhere [12,13]. Strain vs time curves were obtained and the results were analysed in terms of Norton's equation [14], Eq.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Creep Behaviour of Si3N4 Ceramics Sintered with RE2O3

Santos

Strecker

Neto³

et al. 2006

MSF

View full text Add to dashboard Cite

The objective of this work was to evaluate the creep behaviour of Si3N4 based ceramics obtained by uniaxial hot-pressing. As sintering additive, an yttrium-rare earth oxide solid solution, designed RE2O3, that shows similar characteristics to pure Y2O3, was used. Samples were sintered using high-purity α-Si3N4 powder, with additive mixtures based on RE2O3/Al2O3 or RE2O3/AlN, at 5 and 20 vol.%, respectively. The sintered samples were characterized by X-ray diffractometry, scanning electron microscopy and density. Specimens of 3x3x6 mm3 were submitted to creep tests, under compressive stresses between 100 and 350 MPa at temperatures ranging from 1250 to 13750C in air. Samples with RE2O3/Al2O3 showed β-Si3N4 as crystalline phase, with grains of high aspect ratio, and a relative density around 99% of the theoretical density. The Si3N4/RE2O3/AlN samples presented α-Si3N4 solid solution, designed α-SiAlON, with a more equiaxed microstructure and slightly lower relative density (96-98%). The results of creep tests indicated that these ceramics containing α-SiAlON are the more creep resistant, with steady-state creep rates around 10-4 h-1, with stress exponents (n) in the range 0.67-2.53, indicating grain boundary sliding as the main creep mechanism.

show abstract