| Summary: | This research focused on the adhesion properties of mahagony wood from forest
community after heat treatment process. There were two methods of heat treatment which
applied in this study, i.e thermal and hydrothermal methods. The treatment temperatures were
120 ºC, 150 ºC and 180 ºC for 1 and 2 hours. In the hydrothermal process, the specimens
were heated in an autoclave containing water, while in the thermal process, the specimens
were heated in an oven. After the heat treatment process the specimens were then conditioned
for 2 weeks until air-dry condition. In addition , untreated specimens were also prepared as
controls. The test parameters were shear strength, physical and mechanical properties of
untreated and heat-treated woods. Raw materials used in this study were mahogany wood that
obtained from community forest wood in the Yogyakarta area.
The result showed that the variation of heat treatment gave different effect on the
mahogany properties. The interaction between method, temperature and treatment time did
not significantly affect the adhesion properties. Heat treatment method affected very
significantly on the moisture content, color changes, hygroscopicity, modulus of rupture,
modulus of elasticity and density of mahogany. Treatment temperature gave significant effect
on the moisture content, density, color changes, modulus of rupture and modulus of elasticity
of mahogany. The increasing of temperatures and heating times for thermal and hydrothermal
methods resulted the decreasing of water content, density and brightness values of the treated
wood. The thermal method provided the value of mechanical properties higher than untreated
wood. However, the hydrothermal method provided the value of mechanical properties lower
than untreated wood. Adhesion shear strength of the treated woods were lower than that of
untreated wood. The values of adhesion shear strength decreased with the increasing of
temperature and treatment time. The highest and lowest adhesion shear strength values of
treated wood were 132.6 kg/cm2 and 78.66 kg/cm2 respectively, whereas untreated wood was
128.5 kg/cm2. The optimal treatment of mahagony wood was thermal method which treated
at 150 ºC for 2 hours that provided the adhesion shear strength, wood failure, modulus of
rapture, modulus of elasticity, moisture content and specific of gravity were 125.85 kg/cm2,
93.21%, 968 kg/cm2, 77,496 kg/cm2, 9.42% and 0.504, respectively.
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