3D EBSD Based Effective Thermoelastic Properties and Fracture of Silicon Nitride

0435047 - ÚFM 2015 RIV DE eng O - Others
Othmani, Y. - Langhoff, T. - Böhlke, T. - Chlup, Zdeněk - Colonna, F. - Hashibon, A. - Khader, I. - Kailer, A.
3D EBSD Based Effective Thermoelastic Properties and Fracture of Silicon Nitride.
2014
EU Projects: European Commission(XE) 263476 - ROLICER
Institutional support: RVO:68081723
Keywords : Silicon nitride * EBSD * FEM
Subject RIV: JL - Materials Fatigue, Friction Mechanics

Due to the combination of its excellent thermomechanical properties such as high stiffness, strength, toughness and thermal shock resistance, silicon nitride ceramics are prime structural materials for several challenging assignments and applications such as bearings, cutting tools. Silicon nitride consists of two phases: beta-Si3N4 grains (approximately 90 vol. %) and the glassy phase formed by the sintering additives. For a better understanding of the effective theromechanical behavior of silicon nitride ceramics, it is necessary to correlate microstructural and micromechanical properties. Based on finite element simulations of the unit cell (Wippler et al. 2011), using 3D EBSD data of silicon nitride as well as atomistic simulations of the temperature dependence of the elastic proprieties of the local phases, the effective thermoelastic properties are computed and compared to experimental results (Lube and Dusza, 2007). The stress distribution, within the local phases, is determined for different thermomechanical external loadings.
Permanent Link: http://hdl.handle.net/11104/0239594