HIGH TEMPERATURE ELASTIC STRAIN EVOLUTION IN Si3N4-BASED CERAMICS
نویسندگان
چکیده
Tension experiments in vacuum were performed on a monolithic Si3N4 sample at 1375°C and a 20Vol% SiCp-Si3N4 composite sample at 1400°C using the new SMARTS diffractometer at the Los Alamos Neutron Science Center. The deep penetration of neutrons facilitated these in-situ studies. In particular, the hkl-dependent strains were measured and the results interpreted by Eshelby-based modeling for the Si3N4-SiCp sample. The diffraction data also provided information about thermal expansion coefficients for both specimens and the elastic constants at high temperature for the monolithic sample.
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