Infiltration of Reaction-Bonded Silicon Nitride with Equilibrium Y-Si-O-N Melt
نویسنده
چکیده
An equilibrium Y-Si-0-N melt was infiltrated to eliminate the open porosity of reaction-bonded silicon nitride at 16001800°C. This oxynitride melt contained two equilibrium phases, a P-Si,N, solid phase and a liquid phase at high temperatures. Before infiltration, porous reaction-bonded silicon nitride compacts were heat-treated to completely transform to the P-Si3N, phase. After infiltration, the flexural strength of the reaction-bonded silicon nitride material increased from 200 to 600 MPa at 25"C, from 200 to 300 MPa at 1400°C in air.
منابع مشابه
Modelling Temperature Dependency of Silicon Nitride Formation Kinetic during Reaction Bonded Method
An accurate prediction of reaction kinetics of silicon nitridation is of great importance in designing procedure of material production and controlling of reaction. The main purpose of the present study is to investigate the effect of temperature on the kinetics of reaction bonded silicon nitride (RBSN) formation. To achieve this, nitrogen diffusion in the silicon nitride layer is considered as...
متن کاملOxynitride Glasses Prepared from Gels and Melts
The structures of glasses prepared by melting mixtures of alkali borosilicate glass and silicon nitride powders and by ammonolysis of porous borosilicate gels were studied using Fourier transform infrared spectroscopy and combustion analysis. Whereas there was little evidence of nitride bond formation in the melt prepared glasses, Si-N and B-N bonding were observed in the gel-derlved glasses. I...
متن کاملA NEW GENERATION OF OXYNITRIDE GLASSES CONTAINING FLUORINE
Oxynitride glasses are found as grain boundary phases in silicon nitride ceramics. They are effectively alumino-silicate glasses in which nitrogen substitutes for oxygen in the glass network, and this causes increases in glass transition and softening temperatures, viscosities (by two to three orders of magnitude), elastic moduli and microhardness. Calcium silicate-based glasses containing fluo...
متن کاملPartitioning of Si and O between liquid iron and silicate melt: A two-phase ab-initio molecular dynamics study
[1] The magma ocean process in the early history of the Earth has a great influence on the light element identities and contents of the core which subsequently affect the energy of the geodynamo provided by the compositional convection and the inner core growth through their effect on the phase diagram of iron alloy. In the present work, a twophase ab-initio molecular dynamics method is establi...
متن کاملMelting and Processing of Silicon by Microwave Heating
Microwave heating is applied for processing different silicon raw materials, based on the size-, shapeand composition-dependent absorption of radiation of 2.45 and 916 MHz frequency by silicon. In model experiments directed towards the improvement of melting technology, Si-fines and chunks of bulk Silicon from Electronic Grade (EG)and Solar Grade (SG)-silicon production are used as raw material...
متن کامل