Physical, anatomical, and photochemical analyses of some exotic wood species submitted to heat treatment

Abstract

The objective of this study was to evaluate the effect of heat treatment on decorative properties including glossi-ness, color coordinates including lightness (L), blue-yellow (b*) and red-green (a*), hardness (shore-D) morphological characterization and thermal properties of some exotic wood species. Heat treatment of anigre (Aningeria altissima), cedrorana (Cedrelinga catenaeformis), cemara (Casuarina sumatrana) and coronilla (Scutia buxifolia) wood materials were performed in an oven with a programmable controller at 210°C for 3 h. The obtained samples were conditioned in a climate cabin and the decorative properties, morphological characterization with scanning electron microscopy (SEM) and thermal properties with thermogravimetric analyzer (TGA) of the obtained samples were determined. The test results showed that color got darker with heat treatment, specifically L and b* decreased, and a* increased for anigre and cedrorana but a* decreased for cemara and coronilla. The glossiness for all samples generally increased from 20° to 85° but heat treatment decreased the glossiness. The density generally decreased with heat treatment and decrease ratio in the density was found to be in range from 5.6% to 10.6%. According to the SEM analysis, some cracks, pit aspiration and layer decomposition in the micro level of the wood structure were detected. TGA showed that heat treatment makes thermally more stable wood. As a result, it can be said that heat treatment improved the decorative properties of the exotic wood.