Browsing by Author "Karamanoğlu M."

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Effect of Bleaching on Hardness, Gloss, and Color Change of Weathered Woods
(2014-05-01) Budakçı M.; Karamanoğlu M.
The aim of this study was to eliminate the problems of hardness, gloss, and color change of some wood materials exposed to weathering conditions using a bleaching procedure to attempt to return the wood material to its natural state. For this, wood samples of Scots pine (Pinus sylvestris L.), Eastern beech (Fagus orientalis L.), sessile oak (Quercus petraea L.), and chestnut (Castanea sativa Mill.) were exposed to weathering conditions based on 12 months ASTM D-1641, followed by a bleaching procedure using 18% solutions of S1 (NaOH + H2O2), S2 (NaOH + Ca(OH)2), S3 (KMnO4 + NaHSO3 + H2O2), S4 (NaSiO3 + H2O2), and the commercial product S5 (Cuprinol Decking Restorer- (H2C2O4 + C2H4(OH)2). The color, gloss, and hardness changes of samples were determined according to ASTM D 2244-2, EN ISO 2813, and ASTM D 2240 standards. As a result, hardness and gloss values of all woods decreased due to weathering conditions and the wood color turned grey due to degradation. When comparing the weathered samples to the bleached samples, the hardness value was found to be highest in pine wood bleached with the S2 solution, and the gloss value was highest in oak wood bleached with the S1 solution. The greatest color change was found in pine, beech, and chestnut samples bleached with the S4 solution and in oak samples bleached with the S1 solution.
Effect of Treatment Temperature on the Initial Performance of Layers of Water-based Paints in Heat-treated Pine and Beech Wood
(2022-01-01) Karamanoğlu M.; Birinci E.; Kesik H.İ.; Kaymakcı A.
Hardness, surface roughness, and adhesion strength were determined for water-based opaque paints applied to heat-treated wood material surfaces. For this purpose, Scotch pine (Pinus sylvestris L.) and beech (Fagus orientalis Lipsky) woods were used as experimental material. Specimens were subjected to heat treatment at 3 different temperatures (150, 180, and 210 °C) and 2 different periods (2 and 4 h) under laboratory conditions. Two-component water-based paints with commercial codes D17 and D45 were applied to the surfaces. The hardness, surface roughness, and adhesion strength values of painted samples were determined according to the applicable standards. The results showed that there were higher values of hardness and surface roughness of water-based paints in short-term heat treatment compared with long-term heat treatment. A general decrease in pine with D17 and D45 paints applied to the surfaces and in beech with D45 in adhesion strength was detected depending on the increasing heat treatment temperature and duration. An increase was observed in beech samples with D17 paint applied.
Effects of Exposure Time and Temperature on Screw Driving Torques in Heat-Treated Anatolian Black Pine and Sessile Oak Wood
(2022-11-15) Karamanoğlu M.; Tor Ö.
• This study aimed to investigate the characteristics of screw driving torques in heat-treated Anatolian black pine and sessile oak wood. The wood samples were subjected to heat under atmospheric pressure at three different temperatures (130, 180, and 230oC) and two different exposure time levels (2 and 8 h). Screw driving torques of seating and stripping torque (SET and STT) was performed on all samples. The process of screw driving had two main torques, one of which was the seating torque defined as the torque required to clamp parts and the other one was the stripping torque defined as the maximum torque right before the screw strips in the material and the torque drops suddenly because of the formed screw threads being stripped in wood material. Results show that, in both wood species, the SET and STT values decreased due to the increase in heat treatment temperature and exposure time compared to the control groups.
Factors affecting some properties on surface of thermowood material applied with water-based varnishes modifed with nanoparticles
(2021-01-01) Karamanoğlu M.; Kesik H.İ.
Background: The aim of this study is to determine the surface roughness and adhesion strength of water-based varnishes modified with nanoparticles of zinc oxide (ZnO) and hollow ceramic spherical (HCS) against accelerated UV aging effect in some ThermoWood materials. For this purpose, American ash (Fraxinus americana) and scotch pine (Pinus sylvestris Lipsky) wood were heat treated at a temperature of 190 °C for 1.5 hours and 212 °C for 2 hours. The heat-treated samples were applied with two-component water-based varnishes, with D70-D99 commercial codes, modified with 1%, 3% and 5% ZnO and HCS nanoparticles individually then these samples were subjected to accelerated aging for 240 hours according to ASTM G154. The surface roughness of varnish layers was determined by TS 6956 EN ISO 4287/A1 and surface adhesion strength by ASTM D4541 principles. Results: The results showed that the nanoparticles generally decreased the surface roughness and adhesion strength in water based varnishes. But surface roughness increased in additives of 5% HCS in D99 and 1% ZnO in D70. Also adhesion strength increased in additives of 5% ZnO and 1% and 5% HCS in D70. Conclusion: The layer properties of water-based varnishes can be improved with ZnO and HCS nanoparticles against aging effects.
The influence of machining parameters on surface roughness of MDF in milling operation
(2019-01-01) Işleyen Ü.K.; Karamanoğlu M.
This paper examined the effect of machining parameters on surface roughness of medium density fiberboard (MDF) machined using a computer numerical control (CNC) router. The machining parameters such as spindle speed, feed rate, depth of cut, and tool diameter were examined for milling. The experiments were conducted at two levels of spindle speeds, four levels of feed rates, two levels of tool diameters, and two levels of axial depths of cut. The surface roughness values of MDF grooved by CNC were measured with stylus-type equipment. Statistical methods were used to determine the effectiveness of the machining parameters on surface roughness. The influence of each milling parameter affecting surface roughness was analyzed using analysis of variance (ANOVA). The significant machining parameters affecting the surface roughness were the feed rate, spindle speed, and tool diameter (p < 0.05). There was no significant influence of axial depth of cut on the surface roughness. The surface roughness decreased with increasing spindle speed and decreasing feed rate. The value of surface roughness increased with the increase of tool diameter.