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Effect of Feed Speed and Wood Species on Roughness of Machined Surface  [PDF]
?kalji? Nedim,Beljo Lu?i? Ru?ica,?avlovi? Ankica,Obu?ina Mur?o
Drvna Industrija , 2009,
Abstract: In this study, the surface roughness values of planed beech-wood (Fagus L.), oak-wood (Quercus L.) and fir-wood (Abies alba Mill.) specimens were examined. The samples of beech-wood were cut from steamed beech-wood and from thermally modified beech-wood (212oC). The specimens were machined by planing in radial directions with two knives at 6, 12, 18 and 24 m/min feed speed. The cutting depth of 2.0 mm was constant and knife rake angle was 15o. The machining experiments were carried out using a single cutter-block of a Weinig Powermat 400. The cutter-block with a diameter of 125 mm rotated at 6000 revolutions per minute (RPM). Surface roughness was measured from the radial face of each sample according to DIN 4768 (1990) by using Mitutoyo SJ-201 stylus scanner. Comparison between the results of surface roughness of four species showed that surface roughness increases with the increase of feed rate. The surface quality of samples of planed beech-wood, oak-wood and fir-wood were significantly different. The samples of planed surface of oak-wood had the best quality and the samples of fir wood had the highest values of surface roughness. There were no significant differences in the surface quality of thermally modified and steamed beach-wood samples despite the significant difference in mechanical and physical properties of thermally modified and steamed wood.
EFFECT OF FIRE RETARDANTS ON SURFACE ROUGHNESS AND WETTABILITY OF WOOD PLASTIC COMPOSITE PANELS  [PDF]
Nadir Ayrilmis
BioResources , 2011,
Abstract: Surface roughness and wettability of flat-pressed wood plastic composites (WPCs) incorporated with various fire retardants (FRs) (5, 10, or 15% by weight (wt)) at 50 wt-% content of the wood flour (WF) were investigated. The most common FRs, zinc borate (ZB), magnesium hydroxide (MH), and ammonium polyphosphate (APP), were used in the experiments. The WPC panels were made from dry-blended wood flour (WF), fire retardant (FR) powder, and polypropylene (PP) powder with maleic anhydride-grafted PP (2 wt-%) formulations using a conventional flat-pressing process under laboratory conditions. The contact angle measurements were obtained by using a goniometer connected with a digital camera and computer system. Three roughness measurements, average roughness (Ra), mean peak-to-valley height (Rz), and maximum roughness (Ry), were taken from the WPC panel surface using a fine stylus tracing technique. It was found that the surface smoothness of the WPC panels decreased with increasing content of the FR powder while the wettability increased. The control WPC panel without the FR had the smoothest surface, followed by the WPC panels containing the MH, ZB, and APP, respectively.
The Effects of Surface Roughness on Adhesion Strength of Coated Ash (Fraxinus excelsior L.) and Birch (Betula L.) Wood
Justina VITOSYT?,Kristina UKVALBERGIEN?,Gintaras KETURAKIS
Materials Science , 2012, DOI: 10.5755/j01.ms.18.4.3094
Abstract: For the evaluation of surface roughness impact on adhesion properties, the samples of dried ash (Fraxinus excelsior L.) and birch (Betula L.) wood were used. Before wood finishing, the surfaces of the samples were sanded. In order to get different surface roughness the abrasive material of P80, P120, P150, P180, P220 and P240 grit was used. The parameters of surface roughness Ra, Rz and Rmax were measured in three directions: along the wood grain, across the grain and in the angle of 45o. Comparison of the results showed the non-linear dependency of roughness parameters. Afterwards the wood surface was coated with three different acrylic-polyurethane coating systems (1 layer of varnish without primer, 1 layer of primer and 1 layer of varnish, and 1 layer of primer and 2 layers of varnish). The adhesion strength was assessed using the pull-off method. Also the nature of the fracture was evaluated. It was determined that the peculiarities of surface roughness, coating system type and wood species signally results the values of the adhesion strength. DOI: http://dx.doi.org/10.5755/j01.ms.18.4.3094
EVALUATION OF OLD CORRUGATED CONTAINER AND WOOD FIBER APPLICATION ON SURFACE ROUGHNESS OF THREE- LAYER PARTICLEBOARD  [PDF]
Hamideh Abdolzadeh,Kazem Doosthoseini
BioResources , 2009,
Abstract: This paper presents the results of a study to use virgin wood and OCC fiber for particleboard production. Three-layer boards, with wood and OCC fiber on the surface, were fabricated. The type of applied furnishes at surface layers, moisture, and adhesive content were considered as variables, and their effects on roughness of manufactured particleboards were examined. The panels were produced with 10% and 12% urea formaldehyde (UF) adhesive at 10% and 14% moisture content. The surface characteristics were investigated. The results indicated that wood and OCC fiber utilization on the surface layer gave smoother surfaces than a control board with fine wood particles on its surface. The surface roughness decreased as adhesive and moisture content increased.
The Effects of Heat Treatment on the Physical Properties and Surface Roughness of Turkish Hazel (Corylus colurna L.) Wood  [PDF]
Derya Sevim Korkut,Süleyman Korkut,Ilter Bekar,Mehmet Budak??,Tuncer Dilik,Nevzat ?ak?c?er
International Journal of Molecular Sciences , 2008, DOI: 10.3390/ijms9091772
Abstract: Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on the physical properties and surface roughness of Turkish Hazel (Corylus colurna L.) wood were examined. Samples obtained from Kastamonu Forest Enterprises, Turkey, were subjected to heat treatment at varying temperatures and for different durations. The physical properties of heat-treated and control samples were tested, and oven-dry density, air-dry density, and swelling properties were determined. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements, using the stylus method, wereb 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 properties and surface roughness parameters (Ra,Rz, Ry, Rq) for three temperatures and three durations of heat treatment. The results showed that the values of density, swelling and surface roughness decreased with increasing temperature treatment and treatment times. Turkish Hazel wood could be utilized successfully by applying proper heat treatment techniques without any losses in investigated parameters. This is vital in areas, such as window frames, where working stability and surface smoothness are important factors.
The effects of heat treatment on physical and technological properties and surface roughness of European Hophornbeam (Ostrya carpinifolia Scop.) wood
S Korkut, MH Alma, YK Elyildirim
African Journal of Biotechnology , 2009,
Abstract: 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-tovalley 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.
MONITOREO DEL PROCESO DE MAQUINADO DE AROMO AUSTRALIANO (ACACIA MELANOXYLON) CON EMISIóN ACúSTICA Y SU RELACIóN CON LA CALIDAD SUPERFICIAL RESULTANTE WOOD MACHINING PROCESS MONITORING OF BLACKWOOD (ACACIA MELANOXYLON) WITH ACOUSTIC EMISSION TECHNIQUE AND HIS RELATIONSHIP WITH RESULTING SURFACE ROUGHNESS
Alfredo Aguilera,René Zamora
MADERAS : Ciencia y Tecnología , 2007,
Abstract: Se estudia el maquinado paralelo a la fibra (dirección 90-0) de aromo australiano, utilizando transductor piezo-eléctrico para monitorear los niveles de emisión acústica (EA) generados durante el corte, considerando el tipo de madera (albura y duramen), y además la relación con la rugosidad superficial (Rz) obtenida. Como resultados se encontró una adecuada relación entre la modificación de las condiciones de maquinado con la emisión acústica, en la cual un incremento de los espesores promedio de viruta se traducen en un mayor consumo energético durante el corte. Asimismo, se encontraron niveles superiores de emisión acústica al cambiar el tipo de madera de albura a duramen. Finalmente, entre rugosidad superficial y emisión acústica se encontró una correlación muy buena Wood machining parallel to the grain (90-0 direction) of Blackwood was performed using piezo-electrical transducer to record the acoustic emission (AE) signals generated during the cut process, considering the type of wood (heartwood and sapwood), and the relationship with surface roughness (Rz). A good relationship it was found between cutting conditions and acoustic emission signals, where an increase of the chip thickness results in a major consumption of cutting energy. Also, it was detected an increase of AE signals with the change of wood type, passing from sapwood to heartwood (increase of density). Finally, a good relationship it was found between surface roughness (Rz) and acoustic emission (AE)
Fuzzy Linguistic Optimization on Surface Roughness for CNC Turning
Tian-Syung Lan
Mathematical Problems in Engineering , 2010, DOI: 10.1155/2010/572506
Abstract: Surface roughness is often considered the main purpose in contemporary computer numerical controlled (CNC) machining industry. Most existing optimization researches for CNC finish turning were either accomplished within certain manufacturing circumstances or achieved through numerous equipment operations. Therefore, a general deduction optimization scheme is deemed to be necessary for the industry. In this paper, the cutting depth, feed rate, speed, and tool nose runoff with low, medium, and high level are considered to optimize the surface roughness for finish turning based on L9(34) orthogonal array. Additionally, nine fuzzy control rules using triangle membership function with respective to five linguistic grades for surface roughness are constructed. Considering four input and twenty output intervals, the defuzzification using center of gravity is then completed. Thus, the optimum general fuzzy linguistic parameters can then be received. The confirmation experiment result showed that the surface roughness from the fuzzy linguistic optimization parameters is significantly advanced compared to that from the benchmark. This paper certainly proposes a general optimization scheme using orthogonal array fuzzy linguistic approach to the surface roughness for CNC turning with profound insight.
EFFECT OF PINE CONE RATIO ON THE WETTABILITY AND SURFACE ROUGHNESS OF PARTICLEBOARD
ümit Büyüksar?,Erkan Avci,Nadir Ayrilmis,Huseyin Akkilic
BioResources , 2010,
Abstract: In this study, the effect of pine cone ratio on wettability and surface roughness of particleboards was examined. Contact angles of water on the produced samples were measured with a goniometer. The surface roughness of the samples was determined with a fine stylus tracing technique. Particleboards made from 100% wood particle had the lowest average contact angle (95.6°), but the highest was for the particleboards containing 50% pine cone (116.3°). Average surface roughness was higher for samples containing a higher amount of pine cone in the mixture. The smoothest surface (9.77 μm Ra) was observed when panels were produced using 100% wood particles. On the other hand, the roughest surface (15.50 μm Ra) was found for the samples containing 50% cone particles in the mixture. Rmax and Rz parameters had similar trends to the Ra values. Increasing the pine cone ratio in the mixture negatively affected the contact angle and surface roughness parameters of the particleboard.
Measurement of grain surface roughness
Fr???…czek J.,Kaczorowski J.,?…??lipek Z.
International Agrophysics , 2000,
Abstract: In the research on the friction of vegetative grain-structure, an essential problem lies in the appropriate determination of the condition of the surface layer of elements in mutual contact. The analysis must define both tensile strength parameters and the surface topography. Most frequently, surface geometry is defined by roughness. Compared to the traditional methods applied for the construction materials, the measurement of roughness in this case is more difficult due to the cellular structure and multifarious shapes of individual skeletons, while low surface hardness (especially at significant humidity) excludes the possibility of applying mechanical methods. For these reasons, an attempt was made to develop a rapid and simple method for the measurement of grain surface roughness relying on the optical procedure. The measurement bench consists of a stereo-microscope with a trinoculare and a camera linked to the computer through an analogue-digital processor. The entire measurement set is equipped with a MultiScan software, where a special picture processing was applied as described below in the paper. A computer analysis of the picture allows to carry out an automatic and precise measurement of the profile roughness in any selected point on the grain surface.
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