Thermal conductivity of ceramic fibres as a function of temperature andpress load

Abstract

Three ceramic fibres VK-60, ABK and Nextel/VK-80 produced by the steamblowing and nozzle dissemination methods have been investigated for the effectof press load per unit area and temperatures using the transient plane source(TPS) method in air. It was noticed that, with the increase of the aluminiumcontent in the composition of the ceramic fibres, the thermal conductivity of thematerial decreases and the isolation properties improved. TheNextel/VK-80 fibre has the lowest and VK-60 the highest value of thermalconductivity at room temperature.The application of a press load results in an increase in the value of the thermalconductivity for all the fibres analysed. ABK fibres showed the least increase andNextel/VK-80 registered an increase of about 10% in the value of thermalconductivity within the load increase from 0.6 to 6.6 kN m-2. However, above6.6 kN m-2 the thermal conductivity of all the samples increased almostlinearly. The thermal conductivity measurements as a function of temperatureindicated the same trend for an increase in thermal conductivity for all thesamples.