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Selenium (Se) and tellurium (Te) based glasses have unique physical and chemical characteristics that can be manipulated with by the addition of metal alloys. In this study, the thermophysical properties of Se80Te20 and Se80Te10M10 (where M = cadmium (Cd), indium (In), and antimony (Sb)) chalcogenide (containing one or more S, Se, or Te) glasses are investigated to test their use in industrial applications. The transient plane source (TPS) method was used to measure the thermal conductivity, thermal diffusivity, and specific heat of glassy Se80Te20 and glassy Se80Te10M10. Results showed that the glassy Se80Te10In10 alloy had the highest thermal conductivity values, indicating that In is more thermally conductive than Cd and Sb.
Soft tooling processes use flexible polymeric materials to manufacture moulds. However, the malleable materials used for soft tooling, such as silicone rubber, have low thermal conductivities and take an extensive amount of time to cool. In this study, metallic (Aluminum fine powder, grey iron, copper, magnesium, titanium, zinc) and non-metallic (graphite, silicone, glass) thermally conductive filler particles were added to silicone rubber to condense the cooling time of soft tooling methods. The Thermal Constants Analyser measured the thermal conductivity of the filler samples using the transient plane source (TPS) method. Results showed that the thermal conductivity of silicone rubber increased with the volume of filler materials, however certain materials (i.e. copper, Al, graphite, silicon) improved the thermal conductivity more than others. It has been proven that adding any of the aforementioned thermally conductive fillers to silicone rubber will shorten the cooling period of the flexible moulds, and soft tooling processes will become more efficient.
Fiberglass is used inside car mufflers as a noise reducer and insulator. The insulating properties of the fiberglass eliminates the need for muffler heat shields, however to properly design vehicles without heat shields, it is important to know the thermal conductivity of fiberglass at high temperatures. A TPS Thermal Constants Analyzer was used to measure the thermal conductivity of glass fibers with diameters of 17 µm and 24 µm. Each sample was administered 0.1-watts of constant-power heating for 20 seconds, and thermal conductivities were measured up to temperatures of 700 °C. Thermal conductivity increased along a relatively linear trend as the temperature rose except when it followed an increasingly exponential trend between 400 °C to 500 °C. The increase of fiberglass thermal conductivity with raised temperatures could affect their efficacy as vehicular insulators.
Insulation is a vital component in the construction industry, notably in this study, glass wool. Maximizing the hydrothermal performance of glass wool is key when dealing with water vapor, humidity and permeability. Although insulation does not generally come in contact with liquids, it is important to consider all outcomes, with likelihood of accidents occurring and the varying levels of workmanship. The transient technique was employed to thermally characterize glass wool and it was determined to be a function of water. When exposed to water, the thermal conductivity of glass wool was raised by a factor of two. This study alluded to the usefulness of the TSP method when assigning thermal properties to insulating materials.
