Papers by suleyman korkut
The heat treatment of wood is an environment-friendly method for wood preservation. The heat trea... more The heat treatment of wood is an environment-friendly method for wood preservation. The heat treatment process only uses steam and heat, and no chemicals or agents are applied to the material during the process. Tests have shown no harmful emissions are apparent when working with the material. This process improves wood's resistance to decay and its dimensional stability. In this study, the density, compression strength and hardness of heat treated hornbeam (Carpinus betulus L.) wood were investigated. Wood specimens that had been conditioned at 65% relative humidity and 20 ºC were subjected to heat treatment at 170, 190, and 210 ºC for 4, 8, and 12 hrs. After heat treatment, compression strength and hardness were determined according to TS 2595 and TS 2479. The results showed that the decreases of compression strength and hardness were related to the extent of density loss. Both compression strength and hardness decreased with the increasing temperatures and durations of the heat treatment. While the maximum density loss observed was 16.12% at 210 ºC and 12 hour, at these heat-treatment conditions, the compression strength approximately decreased 30% and hardness values in tangential, radial, and longitudinal directions approximately decreased by 55%, 54%, and 38%, respectively. Hence, it was concluded that there might be a relationship between changes of these wood properties.
Drying Technology, 2010
In this study, the effects of heat treatment on color, mass loss, compression strength, and hardn... more In this study, the effects of heat treatment on color, mass loss, compression strength, and hardness of Uludag fir (Abies bornmulleriana Mattf.) were investigated. Wood specimens conditioned at a relative humidity of 65% and a temperature of 20 C were subjected to heat treatment at 170, 190, and 210 C for 4, 8, and 12 h. After heat treatment, compression strength and hardness were determined according to TS 2595 and TS 2479. Color changes were determined according to DIN5033. The results showed that compression strength and hardness of Uludag fir wood decreased to varying extents in relation to intensity of treatment, whereas mass loss increased. We determined that treatment temperature had a more significant effect on color changes than did treatment time. The color of the wood became darker at the higher treatment temperatures.
International Journal of Molecular Sciences, 2008
The mechanical properties of laminated window profiles manufactured using two types of adhesives ... more The mechanical properties of laminated window profiles manufactured using two types of adhesives were determined. The objective of this study is to evaluate the effects of heat treatment on some mechanical properties of laminated window profiles that manufactured from Kosipo (Entandrophragma candollei Harms.) using differenet type adhesives. Commercially produced polyurethane based Macroplast UR 7221 and polyvinyl acetate (PVAc) adhesive were used for experiments. The overall test results were found to be comparable to those obtained in the previous studies. Both types of adhesives resulted in significant differences in their strength characteristics at 95% confidence level. Adhesive UR 7221 improved the overall properties of the samples in contrast to PVAc.
Pigment & Resin Technology, 2011
Design/methodology/approach - Test samples were prepared from Scotch pine, Oriental spruce, and U... more Design/methodology/approach - Test samples were prepared from Scotch pine, Oriental spruce, and Uludag fir, which met the requirements of ASTM D 358. These samples were impregnated with boric acid (Ba) and borax (Bx) using a vacuum technique, according to ASTM D 1413 ...
Building and Environment, 2007
This paper reports the effect of various drying temperatures on the surface roughness (SR) charac... more This paper reports the effect of various drying temperatures on the surface roughness (SR) characteristics of veneer samples. Three SR parameters [average roughness (R a ), average maximum height of the profile (R z ), and root mean square roughness (R q )] were measured on sliced veneer obtained from Oak logs (Quercus petraea ssp. iberica (Steven ex Bieb) Krassiln). The sliced veneers were dried at 100, 115 and 130 1C drying temperatures for 2 min. Roughness measurements were taken from the surface of the samples in across the grain orientation of the veneer. The results showed that the effect of drying temperatures used in practice is statistically significant on SR of the sliced veneers. r
Heat treatment is often applied to some wood species to improve dimensional stability. This study... more Heat treatment is often applied to some wood species to improve dimensional stability. This study evaluated the effect of heat treatment on some physical and mechanical properties and colour of Eucalyptus wood (Eucalyptus camaldulensis Dehn.), which has industrially high usage potential and large plantations in Turkey. Wood specimens from Tarsus, Turkey were subjected to heat treatment in varying temperatures and durations. After the heat treatment, hardness, swelling, ovendry density, and colour change of the wood specimens were tested in comparison with untreated specimens. The results showed that density, swelling, and hardness decreased with increasing treatment temperature and durations while heat treatment made the colour of the wood specimens darker.
Building and Environment, 2008
The effects of some manufacturing factors on surface roughness of sliced Makore´(Tieghemella heck... more The effects of some manufacturing factors on surface roughness of sliced Makore´(Tieghemella heckelii Pierre Ex A.Chev.) and rotary-cut beech (Fagus orientalis L.) Veneers
Industrial Crops and Products, 2011
The aim of this study was to investigate the effect of the thermal modification process by hot-pr... more The aim of this study was to investigate the effect of the thermal modification process by hot-press on the wettability and surface roughness characteristics of the eucalyptus wood boards. The roughness measurements, average roughness (R a ), and maximum roughness (R max ) were taken both parallel and perpendicular to the grain using a fine stylus tracing technique. Contact angle measurements were obtained using a goniometer system connected to a digital camera and computer system. The results showed that surface roughness values of the modified wood boards using a hot-press significantly decreased with increasing press pressure and with decreasing temperature. The contact angle measurements indicated that the thermal modification had a significant influence on the surface wettability of the wood boards. Statistical analyses showed significant differences in the surface roughness and contact angle values of the wood boards following thermal modification. The results acquired in this work provide important information for future research and utilization of the thermally modified wood boards.
Journal of Materials Processing Technology, 2008
The objective of this study was to investigate effects of boiling time on surface roughness of be... more The objective of this study was to investigate effects of boiling time on surface roughness of beech (Fagus orientalis L.) veneer manufactured using the rotary cutting method. Three logs of oriental beech were subjected to softening process by boiling them in water (60-70 • C) for various times (e.g. 20, 40, and 60 h) and they were peeled immediately. For surface roughness, veneer samples were taken from outer, center, and inner (near to pit) parts of logs and the distance of the locations where the samples were taken from the pith were the same. Veneer specimens have a dimension of 10 cm (width) by 20 cm (length) by 0.14 cm (thickness). Three roughness parameters, average roughness (R a ), mean peak-to-valley height (R z ), and maximum roughness (R max ) for each group were measured according to DIN standard 4768 by using stylus profilometer and compared with one another. Except the boiling time, other factors (species, knife angle, peeling angel, etc.) were kept the same. The results show that, the surface of veneers, taken from heartwood and center of the logs boiled 60 h were significantly rougher than 20 and 40 h. But peeling veneers obtained from sapwood of logs boiled 20 h displayed significantly rougher surface than 40 and 60 h. For all samples, applying 40-h boiling period can minimize the roughness value. Therefore, it seems that 40-h boiling period is suitable in order to minimize the surface roughness of rotary-cut veneers manufactured from all of beech (F. orientalis L.) logs parts (inner, center, and outer). .tr (O. Unsal). these factors, surface roughness, is one of the most effective factor on the bonding strength, and the bonding strength decreases when surface roughness increases. It was reported that veneers with the smooth surface resulted in 33% higher adhesive strength than the one with rough surface . Also, the veneers with rough surface requires much more sanding process compared to one with smooth surface, which leads to decrease in thickness of material and, therefore, increase the losses due to the sanding process. Also, the surface roughness of wooden materials is important for the liquid absorption .
World production of wood based panel has grown from 63,1 million cubic meters in 2005 to 75,5 mil... more World production of wood based panel has grown from 63,1 million cubic meters in 2005 to 75,5 million m 3 in 2009, a 12 million m 3 rise in production. China is the world's largest wood based panel's manufacturer. The Turkish wood based panels industry has shown a tendency of fluctuating during this time. Turkey, as the world's 4 th largest producer of wood based panels, is an important contributor to the industry. Turkey has made great strides in the last 20 years in the forest products industry. Both the development of new materials and techniques of domestic and international market demand have played a decisive role. Turkey's wood panel production has gone from 100000 m 3 in the early 2000s, to 5,5 million m³ of production in 2010. The sector's total production capacity is approximately 9 million m³. The results obtained thus far indicate that the Turkish wood based panel industry demand for raw material is not being met by the GDF's chip wood fiber production. Where the raw material supply problem in the industry, as well as the problems encountered in the forest and on the basis of the villagers living adjacent to, not to the time of product problems related to storage and transportation of raw materials and other related problems are bottlenecks. We examine problems related to the provision of raw materials and raw materials research, the need for future estimates of the level at which the world and close to the periphery countries will be examined, wood composite panel production and trade policy recommendations will be developed.
Uploads
Papers by suleyman korkut