A disc of a composite ceramic material composed of silicon nitride (Si3N4) and 20% hBN was prepared and its tribological characteristics were investigated by sliding a Si3N4 pin across its surface at different sliding speeds. The friction coefficient and wear coefficient were determined for the composite using two different test modes: one in which the pin was kept stationary and the disc was rotated on top of the pin, ...
Lutetium aluminum garnet activated by cerium (LuAG:Ce) materials containing functional materials (SiO2 and MgO) were prepared. These materials are used in LEDs, and they require a high thermal conductivity in order to minimize thermal aging. The functional materials were added in order to increase the thermal conductivity, as well as the luminescent properties of these materials. It was found that SiO2 did not improve the luminescent properties, but MgO ...
The thermal and mechanical properties of concrete in which normal weight aggregate has been substituted with lightweight aggregates were investigated. The properties were found to be dependent on the volume fraction of the lightweight aggregate, as well as on the nature and quality of the aggregate. The addition of lightweight aggregates resulted in a decreased thermal conductivity, as well as a decreased thermal diffusivity in all samples. The compressive strength ...
Graphite nano-platelets (GnPs) were dispersed in polyethylene glycol (PEG)/polymethyl methacrylate (PMMA) to form a PEG/PMMA/GnPs composite organic form-stable phase change material. The effects of the incorporation of the GnPs on the morphological, structural, thermal, and electrical properties of the composite were then assessed. The experimental results indicated that the incorporation of the GnPs into the polymer increased the thermal and electrical conductivities, and it was concluded that ...
Si-SiC composite foams were prepared using tannin-based foams as templates. The foams were prepared by four different methods for the determination of which method would best produce a foam with a pore size under 200 µm. The foam samples were characterized by SEM, XRD, and Raman spectroscopy, and the thermal conductivity of one of the foams was investigated by the transient plane source method. It was found that direct infiltration of ...
