FABRICATION AND CHARACTERIZATION OF METAL OXIDE COATING FOR INFRARED REFLECTOR IN STONE CHIP METAL TILE

• Main Author: Zahrah Nawie, Amalia
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/41443
• Institution: Institut Teknologi Bandung

Nowadays, metal tiles are more often used than ceramic tiles because they are cheaper and lighter. This characteristic is suitable for light steel construction which is also increasingly commonly used. Unfortunately metal has good heat-absorbing properties, so that it directly affects the temperature rise inside buildings. This, coupled with the tropical climate condition of Indonesia, causes poor thermal comfort in buildings. Indonesian people tend to use cooling technology such as Air Conditioner (AC) as the preferred solution, but this technology costs too much electrical energy. Thus, a more energy-friendly solution is proposed in the form of cool roof technology using pigmented reflector coating. This layer has a function to reflect near-infrared (NIR) waves, part of the spectrum of sunlight with a wavelength range of 800 nm - 2500 nm which carries energy in the form of heat. In this final project, a dark color pigmented reflector layer with higher NIR wave reflectance was made. This study uses a combination of a mixture of metal oxides in the form of Fe2O3, SiO2, TiO2, and Al2O3 as a constituent layer. The layer were synthesized by the solid-liquid dispersion method to mix metal oxides into polyester resin binder. Several layers have been made with variations in the composition of the metal oxide mass to obtain the largest NIR wave reflectance. Characterization of NIR wave reflection on the surface of the layer were done by using the NIR Spectrometer. Measurement of heat flow from sunlight to the inner surface of the tile is carried out on three sample layers with the best reflectance values, which are applied on the surface of the sandy metal tile, using a pyranometer and a model test system. The measurement results show the largest reflectance of NIR waves, which is 55,7%, obtained from the mass composition of 70% Fe2O3, 12,5% Al2O3, 12,5% TiO2, and 5% SiO2. The measurement results using a mock test show that the tile with the highest reflectance value is able to withstand the rate of heat flow to the inner surface of the metal tile by 38 minutes longer than the tile without the layer with a difference in the average temperature of the two tile surface by 2°C. Measurement with a test model also shows a better ability to withstand heat flow for tiles with bigger thickness based on temperature data at the same irradiation intensity.