Sintering behavior of ultrafine silicon carbide powders obtained by vapor phase reaction

The sintering behavior of ultrafine SiC powder with average particle size of about 0.01-0.06 microns produced by a vapor phase reaction of the Me4Si-H2 system was studied at the temperature range of 1400-2050 deg. It was found that the homogeneous dispersion of C on SiC particles is important to remove the surface oxide layer effectively. B and C and inhibitive effect on SiC grain growth

Development of dynamic deployment simulation of thin composite layer for shape morphing structure

[21st International Conference on Composite Materials] August 20-25, 2017; Xi'an, ChinaThe present study attempted to develop a numerical method to deal with deployment dynamics of a thin composite layer for shape morphing structures, including space deployable structure based on shape memory polymer composites (SMPCs). We utilized a three-layer model based on finite element analysis using shell elements in order to model a thin composite layer. The three-layer model could deal with the difference between tension and bending properties of the thin composite layer.Employing this approach, we also attempted to model our deployment experiment. We observed and simulated the deployment dynamics when one end of the hemispherically curved composite layer was released. When the appropriate bending modulus was used for modeling the composites, the simulated dynamics was almost similar to the experimental results. Therefore, we concluded that the proposed simulation can reproduce the deployment dynamics of a thin composite layer well

Development of microwave diagnostic simulator

Two-dimensional simulator models are presented for microwave diagnostics. The models assume the Maxwell wave equation coupled with the equation of plasma current density in a cold magnetized plasma, which can describe propagation, reflection, and cross polarization scattering of the ordinary and extraordinary modes. The effects of waveguide for the microwave launcher and wall boundary of the vacuum vessel are included in the models. The simulations of ultrashort-pulse reflectometry with the use of incident subcyclic ordinary modes in the models are performed to test the problem of density profile reconstruction