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The effects of
heat treatment on physical and technological properties and
surface roughness of
European Hophornbeam (Ostrya carpinifolia Scop.)
wood
Süleyman Korkut1*,
M. Hakkı Alma2 and Y. Kenan Elyildirim3
1Duzce
University, Faculty of Forestry, Duzce, 81620, Turkey.
2University
of Kahramanmaras Sütçü Imam, Faculty of Forestry,
Kahramanmaras, 46100, Turkey.
3Nuri
Baylar Machine Industry and Tradind Inc., Ankara, Turkey.
*Corresponding author. E-mail:
suleymankorkut@duzce.edu.tr.
Tel: +90
380 5421137. Fax: +90 380 5421136.
Accepted 22 May, 2009 |
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Heat treatment of wood is an effective method to improve the
dimensional stability and durability against biodegradation.
In this study, the effects of heat treatment on physical
properties and surface roughness of
European
Hophornbeam (Ostrya carpinifolia Scop.)
wood were examined. Samples obtained from Alapli-Zonguldak
Forest Enterprises, Turkey, were subjected to heat treatment
at varying temperatures and for varying durations. The
physical properties of heat-treated and control samples were
tested, and oven-dry density, air-dry density, and swelling
properties were determined. The mechanical properties of
heat-treated and control samples were tested, and
compression strength parallel to grain, bending strength,
modulus of elasticity in bending, Janka-hardness (cross-section,
parallel and perpendicular to grain), impact bending
strength, and tensile strength perpendicular to grain were
determined. A stylus method was employed to evaluate the
surface characteristics of the samples. Roughness
measurements by the stylus method were made in the direction
perpendicular to the fiber. Four main roughness parameters,
mean arithmetic deviation of profile (Ra), mean
peak-to-valley height (Rz), root mean square roughness (Rq),
and maximum roughness (Ry) obtained from the surface of wood
were used to evaluate the effect of heat treatment on the
surface characteristics of the specimens. Significant
difference was determined (p = 0.05) between physical and
technological properties, and surface roughness parameters
(Ra, Rz, Ry, Rq) for three temperatures and three durations
of heat treatment. Based on the findings in this study, the
results showed that oven-dry density, air-dry density,
swelling, compression strength parallel to grain, bending
strength, modulus of elasticity in bending, Janka-hardness (cross-section,
parallel and perpendicular to grain), impact bending
strength, tensile strength perpendicular to grain and
surface roughness values decreased with increasing treatment
temperature and treatment times. Increase in temperature and
duration further diminished technological strength values of
the wood specimens.
European
Hophornbeam
wood could be utilized by using proper heat treatment
techniques without any losses in strength values in areas
where working, stability, and surface smoothness, such as in
window frames, are important factors.
Key
words:
Heat treatment, mechanical properties, surface roughness,
European Hophornbeam. |
