Although much research had been conducted to improve the ability of engine cylinder heads to respond to thermal stresses, not much research had been conducted on reducing thermal stresses. The authors set out to determine the thermal conductivity of a commercial aluminum 319 type alloy cylinder head with the future goal of improving the thermal conductivity of cylinder heads to better reduce the stress induced by increasing temperature. The cylinders were ...
Nanocomposites of polyaniline nanofibers reinforced in epoxy were prepared and their ultrasonic velocities, ultrasonic attenuations, and thermal conductivities were measured over a temperature range of 298-373 K. It was found that the ultrasonic velocity decreased with increasing temperature, but increased with increasing concentration of polyaniline nanofibers in the epoxy matrix. These two trends were opposite for the ultrasonic attenuation, and the thermal conductivity was found to increase with increasing temperature ...
Monodisperse hollow silica nanospheres with an outer diameter of ~300nm were prepared for the comparison of thermal conductivity with similar solid silica nanospheres. It was found that the thermal conductivity of the hollow nanospheres was lower than that of the solid silica nanospheres....
In order to test the protective capabilities of body armor, a clay box is placed behind the armor during testing and the penetration depth into the clay is measured after firing. Procedures for the preparation of the Plastilina clay used to make these boxes require that the clay be pre-conditioned in an oven prior to testing. The objectives of this work were to determine if the cooling of the clay ...
Hexagonal boron nitride (h-BN) was used as filler in varying concentrations to form composite polymers with polyactic acid, polyamide, and polyphenylene sulfide. The objective of this work was to produce a composite polymer with a high thermal conductivity for use as electronics packaging. It was determined that although thermal conductivity increased with increasing filler content, it was not necessarily due to the increased number of filler particles present, but rather ...
