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Öğe Determination of fatigue and static strength of scots pine and beech wood(Statny Drevarsky Vyskumny Ustav, 2015) Yildirim, M.N.; Uysal, B.; Ozcifci, A.; Ertas, A.H.In this study, fatigue and static strength of Scots pine (Pinus sylvestris L.) and beech (Fagus orientalis L.) woods were investigated. The fatigue and static strength were conducted using a three point bending test-rig. The specimens were prepared according to ISO 3129 (1975) and fatigue and static bending test were carried out according to ISO 3133 (1975). The fatigue test was carried out at 80, 70, 60, 50 and 40 % stress level that corresponded to specific percentage of material's ultimate strength modulus of rupture (MOR). However the microstructures of fatigue failures were observed by using scanning electron microscope (SEM). The results were indicated that, the fatigue life of Scots pine wood amounted to over 1 million cycle when the stress level was 40 % of MOR for Scots pine and 50 % MOR for Beech. In general, fatigue life decreased as stress level increased and vice versa. The allowable design stress is based on some percentage of MOR for furniture design. On this account, the allowable design stresses for Beech and Scots pine could be set at 50 and 40 % respectively.Öğe The effect of grain angle and species on thermal conductivity of some selected wood species(2011) Yapici, F.; Ozcifci, A.; Esen, R.; Kurt, S.In this study the thermal conductivity of different wood materials was determined. For this purpose, Scots pine (Pinus sylvestris L.), Uludag fir (Abies Bornmülleriana Matff), Oriental beech (Fagus orientalis L), Oak (Quercus robur L.), and Chestnut of Anatolia (Castanea sativa Mill.) woods were used. In the test, the thermal conductivity of the woods was measured according to procedure of ASTM C 1113-99 standards. The lowest thermal conductivity was obtained in the perpendicular direction of Scots pine samples as 0.156 Kcal/mh°C. The highest thermal conductivity was obtained from perpendicular direction of samples in Oriental beech as 0.331 Kcal/mh°C.Öğe Effect of tenon geometry, grain orientation, and shoulder on bending moment capacity and moment rotation characteristics of mortise and tenon joints(Society of Wood Science and Technology, 2012) Likos, E.; Haviarova, E.; Eckelman, C.A.; Erdil, Y.Z.; Ozcifci, A.Bending moment capacity and moment rotation characteristics of mortise and tenon joints as a function of tenon geometry, grain orientation, length, and shoulder fit were examined. Bending moment capacity of all joints in which tenons were fully inserted in mortises was 54% greater than for joints in which tenons were not fully inserted. Jointswith 25.4-mm-long diamond-shaped tenons had greater moment capacity than either rectangular or round tenon joints, whereas joints with 38- or 51-mm-long rectangular tenons had greater capacities than jointswith diamond or round tenons. Similarly, for joints inwhich tenonswere not fully inserted, rectangular tenons had the greatest moment capacity regardless of grain orientation or length. © 2012 by the Society of Wood Science and Technology.Öğe Effects of application methods and species of wood on color changes of varnishes(Academic Journals, 2009) Budakci, M.; Ozcifci, A.; Cinar, H.; Sonmez, A.In this study, the color effects of wood materials to coloring with different application methods (brush, roller sponge and spray gun) and waterborne varnishes were investigated according to ASTM-D 2244. For this purpose, the experimental samples of Scots pine (Pinus silvestris L.), oriental beech (Fagus orientalis L.) and oak (Quercus petreae L.), which are commonly used woods in the carpentry and furniture industry in Turkey, were prepared and varnished with one and two-pack waterborne varnishes in accordance with ASTM D 3023. According to the result of the research, significant color changes in coloring as red and yellow tones on the sample surfaces of varnished wood materials were found. The highest color change was obtained in the samples of oak, when varnished with brush and spray gun while the lowest value was obtained in roller sponge in respect to the application methods for waterborne varnishes. However, the application method of spray gun for self crosslinked polyurethane, topcoat-clear, (SCPt) gave the highest metric chroma value among the three different application methods. © 2009 Academic Journals.Öğe Effects of silica gel on leaching resistance and thermal properties of impregnated wood(2010) Altun, S.; Ozcifci, A.; Senel, A.; Baysal, E.; Toker, H.The aim of this study was to increase the resistance of fire retardant chemicals for leaching in order to improve the fire resistance of wood. For this purpose, Scots pine (Pinus sylvestris L.) and Chestnut (Castanea sativa Mill.) wood impregnated with 3 % aqueous solutions of boric acid, zinc chloride and aluminum chloride at 60 °C by using vacuum- press impregnating method according to ASTM D1413-07 standard. In order to increase leaching resistance of the chemicals, wood samples post-treated with sodium silicate and then sodium bicarbonate to form insoluble silica gel in wood. After leaching test, it was determined that silica gel treatment decreased the amount of leachant in all three impregnation solutions. Effect of silica gel on the thermal behavior of treated samples was determined via termogravimetric analysis (TGA). According to the results of TGA silica gel treatment improved the fire resistance property of wood especially in boric acid treated wood.Öğe Effects of some environmentally-friendly fireretardant boron compounds on modulus of rupture and modulus of elasticity of wood(2009) Toker, H.; Baysal, E.; Simsek, H.; Senel, A.; Sonmez, A.; Altinok, M.; Ozcifci, A.This study was designed to determine some mechanical properties such as modulus of rupture (MOR) and modulus of elasticity (MOE) of wood treated with some environmentally-friendly fire-retardant boron compounds. Sodium perborate (SP) boric acid, (BA), and borax (BX) were used as boron compounds. Wood specimens were prepared from Calabrian pine (Pinus brutiaTen.) and beech (Fagus orientalis Lipski) wood. Before MOR and MOE tests, wood specimens were impregnated with aqueous solutions (1,2, 3,4, 5, and 6 %) of borates according to ASTM D 1413-76. Our results showed that MOR values of wood specimens treated with borates were lower compared to untreated control specimens. The MOR and MOE values of wood specimens were the lowest for treatments with SP followed by BX and BA, respectively. In general, the higher concentration levels of borates, the lower MOR of wood resulted.Öğe The effects of some impregnation parameters on modulus of rupture and modulus of elasticity of wood(2011) Ozcifci, A.; Ayar, S.; Baysal, E.; Toker, H.The aim of this study was to determine the effects of some impregnation parameters such as impregnation chemicals, impregnation durations, and impregnation methods on modulus of rupture (MOR) and modulus of elasticity (MOE) of Oriental beech (Fagus orientalis Lipsky) and Scots pine (Pinus sylvestris L.). Wood specimens were prepared according to TS 2470 and impregnated with chemicals for 2, 4, and 6 hours by dipping and vacuum-pressure methods. Imersol aqua, aqueous solutions of zinc chloride, and borax were used as impregnation chemicals. After impregnation, the MOR and MOE of wood specimens were determined. Results showed that the MOR and MOE of wood specimens were the lowest for the ones impregnated with imersol aqua followed by zinc chloride and borax, respectively. There were no statistically significant differences in MOR and MOE values among all impregnation durations and methods.Öğe Fire properties of laminated veneer lumber treated with some fire retardants(2007) Ozcifci, A.; Toker, H.; Baysal, E.The objective of this study was to determine fire properties of laminated veneer lumber (LVL) prepared from beech (Fagus orientalis Lipsky) veneers treated with some fire retardants. Boric acid (BA), borax (BX), and di ammonium phosphate (DAP) were used as impregnation chemicals, which are the most commonly used fire retardants in wood preservation industry. Tanalith-C 3310 was also used for comparison. Laminated veneer lumbers were manufactured using the melamine formaldehyde (MF) and phenol formaldehyde (PF) adhesives. Fire test method was performed in three stages: flame stage, without flame stage, and glowing stage. Results indicated that the lowest temperature for flame stage, without flame stage, and glowing stage were obtained for the specimens glued with MF and treated with DAP and (BA-BX) mixture. The lowest mass loss was found for the specimens glued with MF and treated with DAP and (BA-BX) mixture. Tanalith-C 3310 didn't improve fire resistance of the LVL specimens.Öğe Glossiness, color stability, and surface roughness of wood treated with some bleaching chemicals(2009) Ozcifci, A.; Yapici, F.; Altun, S.; Toker, H.; Baysal, E.; Senel, A.; Simsek, H.The aim of this study was to determine the effects of different bleaching chemicals and their treatment time on glossiness, color stability, and surface roughness of wood. Spruce (Picea orientalis L.) and oak (Quercus sessiliflora Salisb.) wood specimens were bleached with aqueous solutions of 25% hydrogen peroxide (H2O2), 25% ammonia (NH3), and their mixture (1:1;volume:volume) for 10, 20, and 30 minutes immersing. Glossiness of wood specimens parallel and perpendicular to grain values were measured with Glossmeter at 60-degree incident angle. Color measurements and surface roughness were wade according to ISO 7724 - 2, and ISO 4287 standards, respectively. Results showed that the highest glossiness decrease (0.99) was observed in oak wood treated with ammonia solution perpendicular to grain for 20 min. immersing. The highest total color chance (18.88) was observed in oak wood treated with ammonia solution for 30 minutes immersing. All bleaching solutions increased the surface roughness of wood specimens.Öğe An investigation on compression parallel to grain values of wood impregnated with some boron compounds(2008) Toker, H.; Baysal, E.; Ozcifci, A.; Altinok, M.; Sonmez, A.; Yapici, F.; Altun, S.This study was carried out to determine compression strength parallel to grain of wood impregnated with some boron compounds. Sodium perborate (SP) boric acid, (BA), and borax (BX) were used as boron compounds. Wood specimens were prepared from Calabrian pine (Pinus brutia Ten.) and beech (Fagus orientalis L.) wood. Before compression test parallel to grain, wood specimens were impregnated with aqueous solutions (1, 2, 3, 4, 5, and 6 %) of boron compounds according to ASTM D 1413(1976). Results showed that compression strength parallel to grain values ofwood specimens treated with boron compounds were lower compared to untreated control specimens. Borate treatments reduced compression strength parallel to grain of wood in significant level compared to untreated control. The compression strength parallel to grain values ofwood specimens were the highest for untreated control specimen followed by BA, BX, and SP treated wood specimens, respectively. In general, our results showed that the higher concentration levels of boron compounds, the lower compression strength parallel to grain values of wood resulted.Öğe Some combustion parameters of wood impregnated with borates(2009) Toker, H.; Baysal, E.; Ozcifci, A.; Simsek, H.; Altun, S.; Yapici, F.; Goktas, O.This study was conducted to determine some of the combustion parameters of Calabrian pine and Oriental beech treated with borates. Average mass loss and temperature values of Calabrian pine and Oriental beech wood were determined according to ASTM E-69. Boric acid, borax, and sodium perborate were used as borates. Before the combustion test, wood specimens were impregnated with aqueous solutions (1%, 2%, 3%, 4%, 5%, and 6%) of borates according to ASTM D1413-76. These results showed that mass loss and temperature values of both wood specimens treated with borates were lower compared to the untreated control specimens. Higher concentration levels of borates resulted in lower mass loss and temperature values of the wood. ©Forest Products Society 2009.Öğe Synthesis and characterization of resol type phenol-formaldehyde resin improved by SiO2-Np(Pulp and Paper Research Institute, 2021) Özbay, G.; Kokten, E.S.; Ozcifci, A.In this work, resol type phenol-formaldehyde (RPF) resin was modified with silicon dioxide nanoparticles (SiO2-Np). SiO2-Np was added at varying ratios from 1 to 4 wt.% to improve the bonding performance of the RPF resins. The physical characteristics of the nano-modified RPF (nano-RPF) resins were examined. The effects of modification were studied by Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The results of FT-IR revealed that the nano-RPF resins were successfully produced by phenol, formaldehyde, and SiO2-Np. The nano-RPF resins demonstrated high thermal stability at temperatures above 500°C. The adhesive performance of the nano-RPF resins was investigated under dry and wet conditions. The nano-RPF resins indicated better adhesive performance than unmodified RPF resin. The RPF resin could be improved by SiO2-Np. © 2021 Statny Drevarsky Vyskumny Ustav. All rights reserved.Öğe Technical note: Static versus cyclic load capacity of side chairs constructed with mortise and tenon joints(2013) Likos, E.; Haviarova, E.; Eckelman, C.A.; Erdil, Y.Z.; Ozcifci, A.The effect of cross-sectional tenon geometry on static and cyclic load capacity of side chairs constructed with round-, rectangular-, and diamond-shaped mortise and tenon joints was investigated. Cyclic load capacity averaged about two-thirds of static load capacity for the joint configurations tested. For the configurations included in the test, chairs with mortise and tenon joints constructed with round-, rectangular-, and diamond-shaped tenons had static load to cyclic passing load ratios of 56.5, 66.8, and 69.2% for rectangular-, round-, and diamond-shaped tenons, respectively. These results indicate that useful relationships existed between static and cyclic performance of round mortise and tenon joints, which may simplify the design process for chairs that must pass cyclic performance tests. © 2013 by the Society of Wood Science and Technology.
