Surface characterization of some woods exposed to accelerated weathering

Abstract

In this study, the photo degradation of beech (Fagus orientalis), oak (Quercus robur), ash (Fraxinus spp.), and poplar (Populus euramericana) wood samples were investigated by accelerated weathering test in order to determine the chemical change by Attenuated total reflectance-Fourier transform infrared (ATR-FTIR), surface degradation by Scanning Electron Microscopy (SEM) and colour measurements by portable spectrophotometer. For this purpose, weathering of wood samples was performed in an accelerated weathering tester using ultraviolet irradiation with 0.85 W/m2 at 340 nm for 1000 h. According to results after 168 hours of weathering, the exposed samples showed considerable change in colour, which accompanied with the chemical change in wood components. After that time the total colour change showed a decrease. During the remaining time in weathering process total colour change lowered in comparison to 168 hours. Overall, the highest colour change was obtained with ash samples after weathering. SEM analyses showed cracks on the surface of the wood samples exposed to 1000 hours of weathering.