Thermal interface materials (TIMs) are often used in electronic and microelectronic applications. It can be difficult to determine their characteristics once they are in-situ because it is hard to account for the surface roughness and waviness of the objects the TIM is applied to. This paper explores the application and design of a guarded heat flow meter apparatus that complies with all standards in ASTM D 5470-95 that can accurately ...
Thermal adhesives that contain large proportions of high thermal conductivity filler materials are extremely useful in electronics and manufacturing. Due to the importance of these fillers it is crucial to know their exact properties. Five adhesives are examined for their thermal conductivities. These values were obtained using a guarded heat flow meter with a method following the ASTM test standard. This method ...
This paper introduces a compensation algorithm and a different-layers calibration method that will improve the temperature measurement speed and thermal resistance elimination of a guarded heat flow meter instrument. Without these additions to the method, heat will travel through a thin slice of material too fast for thermal couples to measure accurately. Thermal contact resistance would cause inaccuracy with a thin slice ...
A new analysis method based on the guarded heat flow meter apparatus is proposed to measure the thermal properties of cement-based pastes in a hydrated form. In a steady state, a specimen with 0.4 water-to-cement ratio was found to have a thermal conductivity and a thermal contact resistance of 1.28Wm−1 K−1 and 0.038 m−2 KW−1. A computerized system of heat flow meters provided non-steady ...
The variability within the results presented from the guarded hot-plate (GHP) and guarded heat-flow meter (GHF) methods was determined. Multiple thermal properties of polymethyl methacrylate (PMMA) were analyzed to compare methods. These measurements are taken in the range of −70◦C and +80◦C. Providing reference data for PMMA is the main objective of this paper as well as quantifying the effects of thermal contact of the measuring instruments....