Статті в журналах: "ROUGHNESS OF BLOCKS OF WOOD"

1

Petersson, M. "Noise-related roughness of railway wheel treads-full-scale testing of brake blocks." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 214, no. 2 (March 1, 2000): 63–77. http://dx.doi.org/10.1243/0954409001531342.

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Results from full-scale tread braking experiments on an inertia dynamometer (brake testing machine) are presented. Eighteen prototypes of brake blocks are investigated. Two braking characteristics relating to the influence of the blocks on the wheel tread are studied: generation of hot spots and generation of roughness (corrugation, waviness). Wheel tread temperatures are measured during braking using an infrared (IR) technique. The wheel roughness is measured after each brake cycle when the wheel has cooled down. A roughness indicator, RλCA, relates measured roughness to expected rolling noise as generated by the wheel in operation. A correlation between the spatial distributions of temperatures and roughnesses is normally found: stronger for cast iron blocks and composition blocks and weaker for sinter blocks. The cast iron blocks are found to produce high tread roughness levels, partly owing to material transfer from brake block to wheel tread. The composition blocks are found to result in lower roughness levels than the cast iron blocks. Finally, the sinter metal blocks are found to lead to the lowest roughness levels, a fact which is probably due to the abrasive property of these blocks. Friction coefficients during braking are also measured.

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2

Jankowska, Agnieszka. "Understanding of surface roughness of wood based on analysis its structure and density." Annals of WULS, Forestry and Wood Technology 111 (September 30, 2020): 27–31. http://dx.doi.org/10.5604/01.3001.0014.6421.

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Understanding of surface roughness of wood based on analysis its structure and density. The main aim of presented paper was to investigate the influence the wood density and anatomical details on surface roughness. The scope of study included samples from ten different species of wood (mainly tropical) because of wide range of density and anatomical difference. The results allow to conclude that the roughness of tested wood species demonstrated variation, depending on the wood section and the measurement direction. In general, radial sections showed higher roughness than tangential sections due to interlocked fibres in tested wood species (fibres cut in various ways on the radial section of the wood). Roughness measured perpendicular to the wood fibres were twice as high as those measured parallel to the grain. Wood density was not an important indicator determining surface roughness for tested wood species. The determining element for the roughness measured across the fibres was the diameter of the vessels. Further research is advisable due to the enormous variability of the structure and properties of wood.

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3

Jankowska, Agnieszka. "Understanding of surface roughness of wood based on analysis its structure and density." Annals of WULS, Forestry and Wood Technology 111 (September 30, 2020): 27–31. http://dx.doi.org/10.5604/01.3001.0014.6421.

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Анотація:

Understanding of surface roughness of wood based on analysis its structure and density. The main aim of presented paper was to investigate the influence the wood density and anatomical details on surface roughness. The scope of study included samples from ten different species of wood (mainly tropical) because of wide range of density and anatomical difference. The results allow to conclude that the roughness of tested wood species demonstrated variation, depending on the wood section and the measurement direction. In general, radial sections showed higher roughness than tangential sections due to interlocked fibres in tested wood species (fibres cut in various ways on the radial section of the wood). Roughness measured perpendicular to the wood fibres were twice as high as those measured parallel to the grain. Wood density was not an important indicator determining surface roughness for tested wood species. The determining element for the roughness measured across the fibres was the diameter of the vessels. Further research is advisable due to the enormous variability of the structure and properties of wood.

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4

Ozdemir, Turgay, Ali Temiz, and Ismail Aydin. "Effect of Wood Preservatives on Surface Properties of Coated Wood." Advances in Materials Science and Engineering 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/631835.

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Effect of wood preservatives (waterborne and organicborne) on the performance of surface finishing properties is investigated. Sapwood of scots pine, (Pinus sylvestrisL.), oriental beech (Fagus orientalisLipsky), and chestnut (Castanea sativaMill.) specimens (300 × 100 × 15 mm along the grain) were impregnated with aqueous solution of 2% CCA, 2% Tanalith E, 1% boric acid, and Immersol aqua. Surface roughness, dry film thickness, adhesion strength, gloss measurement, scratch, and abrasion resistance were determined according to related standards for treated and untreated samples. The results indicated that surface roughness and adhesion strength depended on wood species and the chemical composition of preservatives. Generally, waterborne wood preservatives increased the surface roughness of wood while the organic-based wood preservatives decreased it. The organic-based wood preservatives decreased adhesion but they increased gloss value. Wood preservatives did not affect the scratch resistance which was found to depend on properties of the coating. All the wood preservatives increased abrasion resistance.

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5

Evans, Mary Ellen. "Philip Hagreen's Missing Wood Blocks." Chesterton Review 20, no. 2 (1994): 427–28. http://dx.doi.org/10.5840/chesterton1994202/3138.

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6

Gurau, Lidia. "Testing the Processing-Induced Roughness of Sanded Wood Surfaces Separated from Wood Anatomical Structure." Forests 13, no. 2 (February 17, 2022): 331. http://dx.doi.org/10.3390/f13020331.

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The metrology of processed wood surfaces is complex due to the presence of wood anatomical cavities, which are a factor of bias in several metrological steps, from the measuring to the evaluation of the surface quality. Wood requires special recommendations, and one regards the use of a robust Gaussian regression filter for filtering the roughness. The filter was previously tested with success on wood surfaces and was used in this paper. Furthermore, a reliable quantification of the processing roughness requires that independent wood anatomical data be removed from the evaluation. The paper presents a method of separating the roughness induced by processing from the wood anatomical structure. It was tested on different wood species, sanded with various grit sizes, and on a plastic material included for comparisons. The results showed similar values of the processing roughness for materials sanded with the same grit size, in spite of their different structures. The method could further be used for optimization of processing parameters at sanding.

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7

Lunguleasa, Aurel, and Cosmin Spirchez. "Experiments about Roughness of Wood Composites." RECENT - REzultatele CErcetărilor Noastre Tehnice 21, no. 1 (August 24, 2020): 13–18. http://dx.doi.org/10.31926/recent.2020.60.013.

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8

Gurau, L., H. Mansfield-Williams, and M. Irle. "Processing roughness of sanded wood surfaces." Holz als Roh- und Werkstoff 63, no. 1 (November 26, 2004): 43–52. http://dx.doi.org/10.1007/s00107-004-0524-8.

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9

Tan, P. L., Safian Sharif, and Izman Sudin. "Roughness models for sanded wood surfaces." Wood Science and Technology 46, no. 1-3 (October 6, 2010): 129–42. http://dx.doi.org/10.1007/s00226-010-0382-y.

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10

Kúdela, Jozef, Leoš Mrenica, Igor Čunderlík, and Pavel Šmíra. "Morphological Changes on Spruce Wood Surface, Induced by Treatment with Dry Ice." Materials Science Forum 818 (May 2015): 177–80. http://dx.doi.org/10.4028/www.scientific.net/msf.818.177.

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This work concerns the changes to wood surface morphology induced by surface cleaning with dry ice. The surface roughness values demonstrated that the surface treatment with dry ice resulted in amplified surface roughness, mainly due to the increase in the roughness of early wood. The treatment of old wood with dry ice not only guarantees effective removal of contamination from the wood surface, it also induces positive changes in other (such as wettability, surface free energy, color, and similar). This way of wood surface treatment guarantees more wood surface quality for the surface treatment, impregnation or gluing.

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11

İmren, Erol. "Effect of weathering conditions on wood surface roughness: Optimal parameters determined via Taguchi analysis." BioResources 17, no. 4 (October 14, 2022): 6668–78. http://dx.doi.org/10.15376/biores.17.4.6668-6678.

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Wood when exposed to accelerated weathering conditions is deteriorated as a result of factors such as UV rays, temperature, and relative humidity changes. The surface roughness of wood also undergoes substantial changes. In this study, the effect of accelerated weathering conditions on surface roughness changes on Scots pine (Pinus sylvestris L.) and poplar (Populus x euroamericana) wood surfaces were investigated using the Taguchi method. The parameters most affecting the surface roughness were radial direction, 0.5 W/m2 UV, 4 h conditioning time, and 45 min water for Scots pine, and tangential direction, 0.5 W/m2 UV, 2 h conditioning, and 15 min water for poplar wood. The variables that most affected the surface roughness were conditioning with 38% in Scots pine wood and wavelength with 31% in poplar wood.

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12

Gurau, Lidia, Adrian Petru, Anca Varodi, and Maria Cristina Timar. "The influence of CO2 laser beam power output and scanning speed on surface roughness and colour changes of beech (Fagus sylvatica)." BioResources 12, no. 4 (August 22, 2017): 7395–412. http://dx.doi.org/10.15376/biores.12.4.7395-7412.

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The literature provides very little information about engraving or decorating wood using a laser beam. No study was found that considers the surface roughness of wood after such treatments. This paper therefore aimed to find the influence of varying the laser power output and scanning speed of a CO2 laser beam on the surface roughness and colour of beech wood (Fagus sylvatica) for aesthetic applications such as decorative drawing. Laser power outputs from 5.6 to 6.8 W were tested in combination with scanning speeds from 100 to 500 mm/s. The surface roughness was assessed with a robust filter and by following measuring and evaluation recommendations from previous research to reduce the bias from the wood anatomy. The surface roughness measured by a series of roughness parameters (Ra, Rq, Rt, Rk, Rpk, Rvk) and total colour difference DE increased with laser power and decreased with scanning speed. A good correlation was found between surface roughness and wood colour change. Such correlations can be useful for selecting the laser power-scanning speed combinations capable of giving the chosen colour change at a minimum surface roughness.

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13

Pelit, Hüseyin, and Umuthan Arısüt. "Roughness, wettability, and morphological properties of impregnated and densified wood materials." BioResources 18, no. 1 (November 16, 2022): 429–46. http://dx.doi.org/10.15376/biores.18.1.429-446.

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The effects of pre-impregnation on surface roughness, wettability, and morphological structure of densified aspen and fir wood were investigated. Wood specimens were impregnated with paraffin, linseed oil, and styrene after pre-vacuum treatment. The impregnated specimens were densified using compression ratios of 20% and 40% at 120 °C, 150 °C, and 180 °C. The roughness decreased and the contact angle increased in all impregnated specimens (undensified and densified). Compared to paraffin and linseed oil-impregnated specimens, lower roughness and higher contact angle were found in styrene-impregnated specimens. After densification, the roughness and wettability of the wood specimens decreased. More successful results (lower roughness and higher contact angle) were generally obtained in specimens densified with high compression ratio (40%). In both untreated and impregnated specimens, the contact angle increased with increasing compression temperature. While the effect of compression temperature on the roughness of the fir specimens was not significant, the roughness of the aspen specimens (especially styrene-impregnated) decreased with the increase in temperature. Scanning electron microscopy observations indicated that impregnation agents (especially styrene) clung to wood cell walls and partially or completely filled the lumens. This was positively correlated with the determined roughness and wettability. Pre-impregnation facilitated wood densification without significant cell deformations.

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14

Zhong, Zhao-Wei. "Surface roughness of machined wood and advanced engineering materials and its prediction: A review." Advances in Mechanical Engineering 13, no. 5 (May 2021): 168781402110176. http://dx.doi.org/10.1177/16878140211017632.

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This article discusses the surface roughness of wood and advanced engineering materials after machining and its prediction. The topics are surface roughness of precision-machined advanced engineering materials, machining of WC and Inconel, rapidly solidified Al alloys, surface roughness of wood materials, and prediction of surface roughness. Findings include that ductile streaks on silicon and glass surfaces ground or lapped with inexpensive machines largely reduced the polishing time to obtain the required surface roughness. Abrasive jet machining could remove the patterns from recycled wafers and improve the surface roughness. The roughness of WC-Co coatings was significantly improved by using the method of fast regime fluidized bed machining. As beryllium is a toxic element, the rapidly solidified Al alloy may be a good insert material to replace BeCu. Higher bonding strengths resulted from rougher surfaces of wood samples. Wood samples had reduced bonding strengths after soaking in water. Optimum artificial neural networks (ANNs) with necessary inputs could accurately predict the roughness values. ANNs trained using particle swarm optimization and genetic algorithms could predict surface roughness better than typical ANNs. Minimum quantity lubrication is a hot research topic to minimize the amount of the fluid for cost and environmental considerations.

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15

Arnold, Daiana Cristina Metz, Valéria Costa de Oliveira, Claudio de Souza Kazmierczak, Leandro Tonietto, Camila Werner Menegotto, Luiz Gonzaga, Cristiano André da Costa, and Maurício Roberto Veronez. "A Critical Analysis of Red Ceramic Blocks Roughness Estimation by 2D and 3D Methods." Remote Sensing 13, no. 4 (February 21, 2021): 789. http://dx.doi.org/10.3390/rs13040789.

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The method of measuring the roughness of ceramic substrates is not consensual, with unsuccessful attempts to associate roughness with the adhesion of coatings because the ceramic blocks have different areas of contact, shapes, and dimensions of the roughness as well as the extrusion process influences the mechanical anisotropy of the block. The goal of this work is a quantification and comparison of roughness data obtained by 2D and 3D methods, evaluating the variations of results between the measurement methods and formulating a critical analysis regarding the quality of the information obtained with each method. For this propose, four sets of ceramic blocks with different firing temperature were produced, in order to provide groups of blocks with different surface topographies in which the roughness was estimated. The roughness measurements were made in 4608 regions, resulting in 1536 values using 2D method and 3072 values using 3D method. In the 2D method for ceramic blocks, the measurement orientation strongly influences the result, depending on the measurement position and orientation. The 3D method generates a higher average value and allows to identify roughness variations typical of the ceramic block. The roughness estimation of a ceramic block surface must be done using the 3D method.

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16

Keržič, Eli, Boštjan Lesar, and Miha Humar. "Influence of weathering on surface roughness of thermally modified wood." BioResources 16, no. 3 (May 4, 2021): 4675–92. http://dx.doi.org/10.15376/biores.16.3.4675-4692.

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Wood is one of the most important building materials. Thermally modified wood is entering the market and replacing wood preservatives and tropical wood species in some applications. Thermally modified wood is exposed to weathering similarly as other wood-based building materials. It has been reported that if thermally modified wood is exposed to weathering, its moisture performance might decrease fairly fast. Moisture performance reflects the material’s ability to remain dry and dry out fast when wet. The aim of this study was to determine whether this phenomenon is associated with crack formation or roughness. Norway spruce, thermally modified spruce, wax-treated thermally modified spruce, and European larch heartwood samples were exposed to artificial accelerated weathering and natural weathering for 9, 18, and 27 months. Samples were subsequently isolated, and their roughness was determined with a confocal laser scanning microscope on axial and longitudinal surfaces at 10× and 50× magnification. After weathering, roughness increased on both axial and longitudinal surfaces. This was evident from the profile 2D measurements (Ra) and surface 3D measurements (Sa). The effect of natural weathering on roughness was higher than artificial accelerated weathering, presumably due to synergistic effects of abiotic and biotic factors. This may be associated with Wenzel’s theory on the influence of roughness on the contact angles of water on the surface; namely, increased roughness will decrease the contact angle on hydrophilic surfaces.

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17

Rawangwong, S., J. Chatthong, J. Rodjananugoon, W. Boonchouytan, and R. Burapa. "The Study of Proper Conditions in Face Milling Palmyra Palm Wood and Coconut Wood Using Design of Experiment." Advanced Materials Research 488-489 (March 2012): 847–55. http://dx.doi.org/10.4028/www.scientific.net/amr.488-489.847.

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The purpose of this research was to investigate the effects of main factors on the surface roughness in face milling process palmyra palm wood and coconut wood by computer numerical controlled milling machine and using shell end mill cutting tools 6 edges. The main factors including speed, feed rate, depth of cut and angle of cut were investigated for the optimum surface roughness. The result of preliminary trial showed that the depth of cut and the angle of the cut had no effect on surface roughness. It was found from the experiment that the factors affecting surface roughness were feed and speed, with tendency for reduction of roughness value at a lower feed rate and greater cutting speed. Therefore, in the facing process for palmyra palm wood it was possible to determine a face milling condition by means of the equation Ra = 0.954 + 20.4 Feed + 0.00126 Speed. This equation was employed at a limited speed of 800-1200 rpm, and the feed rate of 0.03-0.05 mm/tooth. The result from the experiment of the mean absolute percentage error of the equation of surface roughness is 6.10% which is less than the margin of error, and is acceptable. For coconut wood it was found from the experiment that the factor affecting surface roughness was feed rate and cutting speed, with tendency for reduction of roughness value at lower feed rate and greater cutting speed. Therefore, in the face milling coconut wood it was possible determine a facing condition by means of the equation Ra = 4.72 - 0.000864 Speed + 0.00443 Feed. Leading this equation goes to use is in limitation cutting speed 1000-2000 rpm at feed rate 100-300 mm/min. The result from the experiment of mean absolute percentage error of the equation of surface roughness is 4.64% which is less than the margin of error, and is acceptable. As a result, the selection of optimal machining parameters can be greatly benefited to the Coconut wood furniture manufacturing industry in terms of productivity improvement.

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18

KANG, CHUN-WON, KAZUHARU HASHITSUME, EUN-SUK JANG, and HARADHAN KOLYA. "RELATIONSHIP BETWEEN WOOD ANATOMICAL FEATURES AND SURFACE ROUGHNESS CHARACTERISTICS." Wood Research 68, no. 3 (June 28, 2023): 455–64. http://dx.doi.org/10.37763/wr.1336-4561/68.3.455464.

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This study aimed to investigate the relationship between surface roughness and anatomical features of wood in 15 different species of boards. Surface roughness was measured parallel and perpendicular to the wood grain using a surface profilometer, and anatomical features such as pore size and distribution were analyzed using microscopic techniques. The results showed that surface roughness perpendicular to the grain direction was consistently higher than that parallel to the grain direction for all wood samples. This difference in roughness was correlated with pore size and density. It shows that the larger pores and lower density lead to higher roughness perpendicular to the grain. The study also found that traditional hand planning methods (push and pull) produced a smooth surface finish, with no statistical differences in roughness.

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19

Hakim, Rahman, and Hanifah Widiastuti. "Analisa Hasil Kekasaran Permukaan Kayu terhadap Jenis Ketam." JURNAL INTEGRASI 9, no. 2 (October 26, 2017): 119. http://dx.doi.org/10.30871/ji.v9i2.455.

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A plane is a tool related to woodworking, which is used for smoothening the surface of the wood. Currently, there are many different smoothing planes available in the market. In this study, the evaluation of a self-made hand plane was conducted. One of the variables that can be utilized to investigate smoothing plane’s performance is by analyzing its wood’s surface smoothening capability. In this reserch, the smoothening capability was evaluated by measuring the wood’s surface roughness after the smoothening process. This study was conducted by utilizing three different types of wood namely limestone wood, meranti wood, and kempas wood as well as three different planes that are a mini plane (self-made tool), a commercial plane, and a power planer. The results show that prior to smoothening process, the maximum surface roughness was 16.432 µm for wet limestone wood and the minimum was 7,871 µm for kempas oven wood. After the smoothening process, the surface maximum roughness values are 10,932 µm using hand mini plane, 12,329 µm for kapur basah wood with the commercial plane for kapur basah wood and minimum roughness of 4,982 µm obtained hand mini plane for meranti oven wood and 5,826 µm for meranti oven wood with the commercial plane. It was also observed that the self-made mini plane gave lower values of surface roughness compared to commercial plane. Thus, it could be summarized that the self-made plane (mini hand plane) is capable to be used for the wood surface smoothening and it has better performance compared to the commercial plane.

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20

Pelit, Hüseyin, and Özkan Yaman. "Influence of processing parameters on the surface roughness of solid wood cut by abrasive water jet." BioResources 15, no. 3 (June 24, 2020): 6135–48. http://dx.doi.org/10.15376/biores.15.3.6135-6148.

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The surface roughness of pine, beech, and oak wood cut in the abrasive water jet (AWJ) system was evaluated for different processing parameters. Wood specimens were prepared in thicknesses of 18, 36, and 54 mm in both tangential and radial directions. Then the specimens were cut, applying three different feed speeds (50, 100, and 200 mm/min), three different abrasive flow rates (200, 300, and 450 g/min), and two different cutting liquid pressures (300 and 380 MPa) with the AWJ system. The Ra and Rz roughness values were higher in the tangential cut for pine and oak specimens and in the radial cut for beech wood. Roughness values increased in all specimens with increases in the AWJ feed speed and the wood thickness. In contrast, with increased amounts of abrasive, Ra and Rz values of the specimens decreased and surface smoothness tended to increase. Roughness values of pine and oak specimens generally decreased due to the increase in liquid pressure. However, an increase in the roughness of the beech specimens was determined. As a result, the feed speed and wood thickness were the most influential parameters on the roughness of specimens. In contrast, the cutting direction and liquid pressure showed less importance on the roughness.

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21

Gurau, Lidia, Mark Irle, and Julia Buchner. "Surface roughness of heat treated and untreated beech (Fagus sylvatica L.) wood after sanding." BioResources 14, no. 2 (April 22, 2019): 4512–31. http://dx.doi.org/10.15376/biores.14.2.4512-4531.

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The effect of sanding, as the last operation before finishing, on the quality of heat treated wood surfaces has been insufficiently explored and explained. This paper compared the effects of sanding with three commonly used sanding grit sizes P60, P100, and P150 on the surface roughness values of beech (Fagus sylvatica L.) wood. The wood samples were treated by the ThermoWood process at 200 °C for 2.5 h. A large range of standard roughness parameters (Ra, Rq, Rv, Rt, RSm, Rsk, Rk, Rpk, and Rvk) and two waviness parameters (Wa, and Wt) were included in the analysis, as well as environmental scanning electron microscope (ESEM) images of the sanded surfaces. The results showed that the heat treatment slightly increased the surface roughness and decreased the wood surface waviness after sanding. All roughness and waviness parameters increased with increasing sanding mean grit diameters by following a strong linear correlation. The processing roughness was closely approximated by the parameter Rk. For both, treated and untreated beech, sanding had a tendency to obscure (in magnitude and number) wood anatomical details in the measured data. However, the influence of wood anatomy in the valleys domain increased as the grit size became finer.

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22

Kamperidou, Vasiliki, Efstratios Aidinidis, and Ioannis Barboutis. "Impact of Structural Defects on the Surface Quality of Hardwood Species Sliced Veneers." Applied Sciences 10, no. 18 (September 9, 2020): 6265. http://dx.doi.org/10.3390/app10186265.

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The surface roughness constitutes one of the most critical properties of wood and wood veneers for their extended utilization, affecting the bonding ability of the veneers with one another in the manufacturing of wood composites, the finishing, coating and preservation processes, and the appearance and texture of the material surface. In this research work, logs of five significant European hardwood species (oak, chestnut, ash, poplar, cherry) of Balkan origin were sliced into decorative veneers. Their surface roughness was examined by applying a stylus tracing method, on typical wood structure areas of each wood species, as well as around the areas of wood defects (knots, decay, annual rings irregularities, etc.), to compare them and assess the impact of the defects on the surface quality of veneers. The chestnut veneers presented the smoothest surfaces, while ash veneers, despite the higher density, recorded the highest roughness. In most of the cases, the roughness was found to be significantly lower around the defects, compared to the typical structure surfaces, probably due to lower porosity, higher density and the presence of tensile wood. The results reveal that the presence of defects does not affect the roughness of the veneers and increases neither the processing requirements of the veneer sheets before finishing, nor the respective production cost of veneers and the veneer-based wood panels. The high utilization prospects of the examined wood species in veneer production, even those bearing various defects, is highlighted.

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23

Miklečić, Josip, and Vlatka Jirouš-Rajković. "The Relationship between Roughness of Finished Wood Floors and Slip Resistance." Drvna industrija 72, no. 1 (February 11, 2021): 49–56. http://dx.doi.org/10.5552/drvind.2021.2009.

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The present study investigates the relationship between the roughness of beech wood and oak wood surfaces treated with oil and polyurethane coating and the slip resistance in dry, water-wet and oily conditions. Pendulum tests were conducted for slip resistance assessment, and roughness measurements were performed by stylus instrument using Ra, Rt, Rp, Rz and Rsm parameters for surface roughness evaluation. Slip potential in dry conditions was low for all finished wood floors studied. Contamination of the surface with water and oil reduced the slip resistance of finished oak and beech flooring. The strong negative correlation was found between slip resistance on dry finished flooring and roughness parameters Ra, Rz, Rt and Rp, and positive correlation between slip resistance on water-wet finished flooring and roughness parameters Ra, Rz, Rt and Rp. Moreover, the correlations between roughness parameters Ra, Rt, Rp and Rz and slip resistance were very similar, and the roughness parameters correlated more strongly with the slip resistance on dry and water-wet surfaces than with the slip resistance on oil-wet surface. Comparison of the slip potential classifications of finished wood floors based on pendulum data and based on Rz surface roughness parameters showed that in some cases the Rz parameter appeared to overestimate the slip potential of the floors in wet conditions. The results confirm previous research that roughness measurements should only be used as a guide and should not be used as the only indicator of the slip potential of wood flooring materials.

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24

Huang, Congxun, Guoqi Xu, Lihai Wang, Ping Zhang, Pengwei Zhao, and Yan Zhong. "Antagonistic Properties and Screening of Bacillus Velezensis Nhw-B72 against Wood Fungal Decay." Forests 12, no. 6 (June 15, 2021): 785. http://dx.doi.org/10.3390/f12060785.

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(1) Background: Wood decay is a serious issue that results from the presence of wood-destroying fungi and has a great influence on the international wood industry. The utilization of biological control methods offers good prospects for wood preservation. (2) Methods: The plate-screening experiment, the soil block test of the Chinese stand method (GB/T 13942.1), and the characterization of wood blocks were used to achieve biological control of brown rot and white rot. (3) Results: Through isolation, screening, and identification, the antagonistic bacterium Bacillus velezensis Nhw-B72 strain was obtained. In the plate-screening experiment, the inhibition zone diameter of Nhw-B72 for Gloeophyllum trabeum was 1.68 cm and that for Coriolus versicolor was 2.33 cm. After inhibition, the morphology of mycelia was distorted, malformed, and broken. In the soil block test, the average weight loss percentage of wood blocks in the control group was 61.66%. In the treatment group, the average weight loss percentage of the wood blocks with drying was 28.18% and that of the wood blocks without drying was 34.97%. (4) Conclusions: The strain has an obvious antagonistic effect on the wood-destroying fungi and the sterile fermentative liquid can effectively inhibit wood decay. In addition, compared to the drying of wood blocks, the air-drying of blocks after impregnation with the fermentative liquid had a better inhibition effect.

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25

Choi, Heung Sik. "An Estimation of Roughness Coefficient in a Channel with Roughness Correction Blocks." Journal of the Korean Society of Civil Engineers 34, no. 1 (2014): 107. http://dx.doi.org/10.12652/ksce.2014.34.1.0107.

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26

Białowąs, Barbara, and Karol Szymanowski. "Effect of thermomechanical densification of pine wood (Pinus sylvestris L.) on cutting forces and roughness during milling." Annals of WULS, Forestry and Wood Technology 113 (March 31, 2021): 36–42. http://dx.doi.org/10.5604/01.3001.0015.2330.

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Effect of thermomechanical densification of pine wood (Pinus sylvestris L.) on cutting forces and roughness during milling. The paper presents the results of research concerning the assessment of machinability of pine wood thermomechanically compacted. The assessment was made on the basis of the cutting forces and surface roughness after the milling process. Selected properties of native and modified wood were examined. Based on the research, it was found that compacted wood is characterized by higher cutting forces during milling. The surface quality after milling was examined and the roughness index Ra values were determined. The research shows that the modified wood is characterized by a lower Ra value both along and across the grain. Statistical analysis showed that the modification had a statistically significant effect on the values of cutting forces and the physical and mechanical properties of the tested wood.

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27

Okumura, Shogo, and Yuko Fujiwara. "Roughness Evaluation of Machined Surfaces of Wood." Mokuzai Gakkaishi 53, no. 4 (2007): 173–79. http://dx.doi.org/10.2488/jwrs.53.173.

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28

Engøy, Thor, Knut Jørgen Måløy, Alex Hansen, and Stéphane Roux. "Roughness of Two-Dimensional Cracks in Wood." Physical Review Letters 73, no. 6 (August 8, 1994): 834–37. http://dx.doi.org/10.1103/physrevlett.73.834.

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29

Piernik, Magdalena, Grzegorz Pinkowski, and Andrzej Krauss. "Effect of chip thickness, wood cross-sections, and cutting speed on surface roughness and cutting power during up-milling of beech wood." BioResources 18, no. 4 (August 4, 2023): 6784–801. http://dx.doi.org/10.15376/biores.18.4.6784-6801.

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Анотація:

The aim of the conducted experiments was to determine the effect of selected machining parameters on power consumption and surface quality obtained during the milling of beech wood using a computerized numerical control woodworking machine. Surface roughness was tested using the contact roughness measurement method, while roughness parameters Ra and Rz were recorded and cutting energy was determined. Tests were conducted for two variants of cutting speed (7.5 and 15 m·s-1) as well as three variants of chip thickness (0.10, 0.06, and 0.02 mm); additionally, the tests examined different cross-sections of wood. It was found that greater chip thickness and feed speed caused an increase in surface roughness and cutting power. In turn, cutting speed had no effect on surface roughness, whereas its increase resulted in increased cutting power. Surface roughness at the radial and tangential cross-sections was comparable, while it was greater at the transverse cross-section. It was also found that cutting power was lowest at the radial cross-section, while it was greater at the tangential and the greatest at the transverse cross-section.

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30

Nascimento, Maria Fátima do, André Luis Christoforo, Juliano Fiorelli, Luciano Donizeti Varanda, Laurenn Borges de Macedo, and Francisco Antonio Rocco Lahr. "Roughness study on homogeneous layer panels manufactured from treated wood waste." Acta Scientiarum. Technology 39, no. 1 (February 24, 2017): 27. http://dx.doi.org/10.4025/actascitechnol.v39i1.29438.

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Natural resource exploration is growing, highlighting woods and joinery waste, wood industries and the like. This study presents homogeneous particleboard (PPH) roughness characterization manufactured from treated wood waste. Normative document with values of Brazilian Technical Standard Association ABNT NBR 8404 (1984), was adopted as a reference. The results show that the manufactured PPH showed roughness class N 10, with roughness values (Ra) of less than 12.5 microns.

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31

Ratnasingam, Jegatheswaran, Hazirah Ab Latib, Lim Choon Liat, and Saeid Reza Farrokhpayam. "Comparative steam bending characteristics of some planted forest wood species in Malaysia." BioResources 17, no. 3 (July 7, 2022): 4937–51. http://dx.doi.org/10.15376/biores.17.3.4937-4951.

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The bending performance of wood is important for its application in furniture, and it is one of the criteria used to assess the suitability of a particular wood species for furniture. In this context, the steam-bending and surface roughness characteristics of four forest plantation wood species were evaluated. One batch of wood specimens were subjected to both surface roughness experiments using the stylus and toluene spread methods, while another batch of the wood specimens were subjected to steaming, clamped, and bent using a circular shape mold. The instantaneous spring-back was measured after 10 days, while the spring-back over time was measured from days 15 to 65. The surface roughness experiments showed that the Hevea brasiliensis had the lowest surface roughness, followed by the Eucalyptus pellita, Acacia mangium, and finally Revotropix paulownia. In terms of the bending performance, it was found that only the H. brasiliensis achieved the threshold 95% satisfactory level based on visual ranking. Furthermore, the wood species also recorded the lowest spring-back, both instantaneous and over-time, to register the best bending performance. On the other hand, R. paulownia had the worst bending performance, primarily due to its low density.

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32

Mononen, Kirsi, Leila Alvila, and Tuula T. Pakkanen. "Changes in color and structure of birch wood (Betula pendula) caused by bleaching with hydrogen peroxide solution." Holzforschung 59, no. 1 (January 1, 2005): 59–64. http://dx.doi.org/10.1515/hf.2005.010.

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Abstract The effect of bleaching with a hydrogen peroxide (H2O2) solution on coloring of secondary xylem of kiln-dried birch wood (B. pendula) was investigated with CIELAB color measurements. Structure of unbleached and bleached wood pieces was studied by light microscopy (LM), environmental scanning electron microscopy (ESEM), and transmission electron microscopy (TEM). In addition, hardness and surface roughness of unbleached and bleached wood pieces were characterized with Brinell hardness and contact angle measurements. The results indicated that surface bleaching with H2O2 solution changed the color of birch wood toward white and less red, simultaneously increasing the porosity and roughness of the uppermost surface as well as decreasing the hardness of bleached wood pieces. With embedding bleaching for 24 h with H2O2, the color of the wood pieces could be changed further; however, microscale defects were detected in fiber secondary cell walls. Consequently, complementary to results obtained from microscopic studies, lower hardness values supported the degradation of fiber secondary cell wall in bleached wood pieces. In addition, contact angle measurements indicated increased surface roughness of wood pieces after embedding bleaching with H2O2.

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33

Krystofiak, Tomasz, Ahmet Can, and Barbara Lis. "Investigation of Roughness and Adhesion Strength Properties of Pine and Poplar Wood Heat Treated in Air and under Vacuum after Artificial Aging." Coatings 12, no. 12 (December 6, 2022): 1910. http://dx.doi.org/10.3390/coatings12121910.

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Анотація:

Heat treatment is an eco-friendly and efficient way to improve the defective properties of wood, such as its hygroscopic nature, the lack of dimensional stability, and low resistance against biological degradation, and to produce a green and sustainable wood material for construction and buildings. However, these treatments alter the substrates and could influence the performance of the coating products necessary to maintain the surface features in certain end-use sectors. In this study, the effects of heat treatment in air (HT) and under vacuum (VHT) on the surface properties of Scots pine (Pinus sylvestris L.) and poplar (Populus euramericana) wood were investigated. For this purpose, the samples were exposed to an artificial aging process. After the aging process, surface roughness and the adhesion strength behavior of the samples were measured. After the HT and VHT, poplar and pine wood samples showed different roughness. While the roughness value parallel to the fibers decreased in poplar wood, it increased in pine wood. The roughness value perpendicular to the fibers increased in both tree species. The maximum roughness value after UV aging was 62,622 in the VHT-200 group. Although with the UV ageing treatment, the adhesion strength was decreased in the samples heat treated in air, it was increased in the samples subjected to vacuum heat treatment. A lower loss of adhesion strength was observed in the heat-treated samples processed under vacuum compared to the heat-treated samples processed in air.

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34

Möttönen, V., A. Asikainen, P. Malvaranta, and M. Öykkönen. "Peroxide Bleaching of Parquet Blocks and Glue Lams." Holzforschung 57, no. 1 (January 8, 2003): 75–80. http://dx.doi.org/10.1515/hf.2003.012.

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Summary The lack of a suitable method on an industrial scale has so far restricted the use of bleaching of solid wood in the woodworking industry. In this study, a new method ‘Wood-Brite™’, based on bleaching solid wood blocks with hydrogen peroxide solution, was investigated. According to our measurements, the lightness of all the wood species studied could be increased and the increase could be controlled by the intensity of peroxide treatment. Differences were observed in the change of chroma and hue of different wood species. Redness usually decreased regardless of the treatment intensity, except with teak, in which it increased markedly. At every treatment intensity, the yellowness of originally light birch wood decreased, but in other wood species it increased.

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35

Su, Chu Wang, Jing Da Huang, Jian Ju Luo, Lian Lai, and Yuan Yi Wuang. "Optimization of Sanding Parameters for Wood Surface of Plantation-Mytilaria laosensis." Advanced Materials Research 538-541 (June 2012): 1360–64. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1360.

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Анотація:

In order to analyze the relation between wood surface roughness of plantation-Mytilaria laosensis and sanding parameters, two orthogonal experiment were performed. The results show that the mesh of the sandpaper has remarkable influence on wood surface roughness of plantation-Mytilaria laosensis,but the feeding speed and sanding thickness don’t; when the mesh of the sandpaper is 150, the feeding speed is 7 m/min and sanding thickness is 0.6 mm during the first sanding and the mesh of the sandpaper is 240, the feeding speed is 8m/min and sanding thickness is 0.15mm during the second sanding, the smallest roughness (Ra) was obtained as 2.79μm. Considering production efficiency, changing feeding speed into 9 m/min in the theory optimization scheme, engineering optimization scheme was obtained, and the wood surface roughness (Ra) is 2.80μm.

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36

Wei, Weihua, Rui Cong, Tongming Xue, Ayodele Daniel Abraham, and Changyong Yang. "Surface roughness and chip morphology of wood-plastic composites manufactured via high-speed milling." BioResources 16, no. 3 (July 1, 2021): 5733–45. http://dx.doi.org/10.15376/biores.16.3.5733-5745.

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Анотація:

Wood-plastic composites have attracted extensive attention throughout the world because of their advantages. However, the manufacturing mechanism of the wood-plastic composites, i.e., high-speed milling technology, is not perfect and needs further study. The effects of the cutting parameters, i.e., the spindle speed, feed rate, axial milling depth, and radial milling depth, on the surface roughness and chip morphology were studied; the surface roughness values, Ra and Rz of high-speed milling wood-plastic composites samples were measured via high precision surface roughness measuring instrument, and their regression equations were calculated. The chips produced via a high-speed milling process were collected and studied. The results showed that the surface roughness of the wood-plastic composites increases with an increase in the axial depth, feed rate, or radial depth, but decreases with an increase in the spindle speed. In addition, the axial milling depth, feed rate, and spindle speed had a significant effect on the morphology of the chips. However, the effect of the radial milling depth on the morphology of the chips was not obvious. The results can provide a scientific basis for the optimization of high-speed milling processing of wood-plastic composites.

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37

Altay, Çaglar. "Weathering Performance of Oriental Beech (Fagus orientalis L.) Wood Impregnated with Glycerol and Glyoxal." Drvna industrija 74, no. 2 (June 20, 2023): 213–21. http://dx.doi.org/10.5552/drvind.2023.0054.

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Анотація:

This study aimed to improve some surface properties such as color, gloss, and surface roughness changes of Oriental beech (Fagus orientalis L.) wood impregnated with some water repellent chemicals such as glycerol (GR) and glyoxal (GX) after weathering. Oriental beech wood specimens were impregnated with a 4 % aqueous solution of GR, GX, and a mixture of GR and GX (1:1; weight : weight) (GR+GX) and then exposed to weathering in Muğla Province in Turkey. Results showed that [delta]L* values of all wood specimens were decreased after weathering. Moreover, the decreases in the control specimen were higher than in the impregnated wood specimens. Oriental beech wood specimens showed a greenish and yellowish tendency, giving -[delta]a* and +[delta]b* values, respectively. Total color changes of GR impregnated Oriental beech was the lowest after weathering. The gloss of all Oriental beech test specimens decreased after weathering. The control specimen gave the lowest value in all three surface roughness parameters (Ra, Rz, and Rq) after weathering. Among the impregnated specimens, the groups impregnated with GR had, in general, the highest value in all three roughness degrees and showed the most negative results in surface roughness.

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38

SMAJIC, Selver, and Juraj JOVANOVIC. "INFLUENCE OF DIFFERENT MACHINING ON THE ROUGHNESS OF OAK WOOD." Series II: Forestry Wood Industry Agricultural Food Engineering 14(63), no. 1 (June 1, 2021): 101–8. http://dx.doi.org/10.31926/but.fwiafe.2021.14.63.1.9.

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The paper presents research on the differences the in total roughness and the impact of parameters during different kinds of machining processes of oak samples. Oak wood samples were planed referring to a radial surface structure of wood. The planing machine was Weinig Unimat 500 and the planing head had two blades. The planing was conducted at a feed speed of 10, 15, 20, 25, and 30 m·min-1. The cutting depth of the machining grip was 1.00 mm and the rake angle of the tool blade was bio γ = 15°, at 6000°/min. The diameter of the cutting blade was Φ = 125 mm. Sanding was performed on a Viet Opera V contact sanding machine in combination heads with pre-planing knives and a roller with sanding belt. Roughness was measured along the grain in the latewood area of the annual growth using the electro mechanical profiler Mitutoyo SJ-500. The samples which were machined at a feed speed of 10 m·min-1 had the lowest roughness. The highest value of the roughness had samples which were machined at a feed speed of 30 m·min-1. After comparing roughness obtained during sanding and planing it was determined that the surface roughness obtained on a sanding machine approximately corresponds to the roughness obtained by planing at a feed speed of 20 and 25 m·min-1.

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39

Li, Guangyao, Qinglin Wu, Yanli He, and Zhikun Liu. "Surface roughness of thin wood veneers sliced from laminated green wood lumber." Maderas. Ciencia y tecnología, ahead (2018): 0. http://dx.doi.org/10.4067/s0718-221x2018005001101.

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40

Su, Chu Wang, Jing Da Huang, Jian Min Zhang, Yi Ren, and Ze Kun Wang. "Optimization of Sanding Parameters for Surface of Laminated Veneer Lumber of Eucalyptus." Applied Mechanics and Materials 189 (July 2012): 21–25. http://dx.doi.org/10.4028/www.scientific.net/amm.189.21.

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Анотація:

In order to analyze the relation between wood surface roughness of Laminated Veneer Lumber of Eucalyptus and sanding parameters, an orthogonal experiment and a single factor experiment were performed. The results show that the mesh of the sandpaper has remarkable influence on wood surface roughness of Laminated Veneer Lumber of Eucalyptus, but the feeding speed and sanding thickness don’t; when the mesh of the sandpaper is 150, the feeding speed is 6 m/min and sanding thickness is 0.6 mm during the first sanding and the mesh of the sandpaper is 320, the feeding speed is 9m/min and sanding thickness is 0.2mm during the second sanding, the smallest roughness (Ra) was obtained as 2.45μm. Considering production efficiency, changing feeding speed into 9 m/min, engineering optimization scheme was obtained, and the wood surface roughness (Ra) is 2.70μm.

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41

Pinkowski, Grzegorz, Waldemar Szymański, Andrzej Krauss, and Stanisław Stefanowski. "Effect of sharpness angle and feeding speed on the surface roughness during milling of various wood species." BioResources 13, no. 3 (July 27, 2018): 6952–62. http://dx.doi.org/10.15376/biores.13.3.6952-6962.

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Анотація:

The article presents research on the effect of the sharpness angle on the quality of machined surface of native wood species (pine, beech, and black locust) and an exotic species called iroko. Four sharpness angle values were analyzed at 25, 40, 45, and 55°. The experiment was conducted on a bottom-spindle milling machine, with a constant spindle rotational speed (6000 min-1) and four feeding speeds of 3.2, 8.3, 12.5, and 16.7 m/min. The influence of sharpness angle, feeding speed, and wood species on the quality of machined surface of wood was determined. The optimum ranges of the sharpness angle were established with respect to wood surface quality. The surface roughness of the samples decreased with decreasing in the sharpness angle in range of 55° to 40°. The optimal value of the angle was 40°, and the roughness increased with increasing feeding speed. It was found that an increase in wood density decreased surface roughness.

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42

Szymanowski, Karol, and Daniel Gruszczyński. "Effect of thermomechanical modification of Scots pine (Pinus sylvestris L.) wood on machine sanding efficiency." Annals of WULS, Forestry and Wood Technology 118 (July 25, 2022): 74–84. http://dx.doi.org/10.5604/01.3001.0016.0856.

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Анотація:

Effect of thermomechanical modification of Scots pine (Pinus sylvestris L.) wood on machine sanding efficiency. The aim of this study was to investigate the effect of thermomechanical modification of pine wood (Pinus sylvestris L.) on the efficiency of machine sanding. For this purpose, pine wood samples (undensified and densified) were subjected to mechanical sanding. The effect of the modification on the mass loss in the sanding process was investigated and the quality of the obtained surface was examined. Roughness parameters Ra and Rz were used as criteria for the quality of the sanded surface. The study was carried out for three different grit sizes of sanding paper. It was found that the thermomechanical modification of Scots pine wood had a statistically significant effect on the mass loss during sanding and the roughness of the obtained surface. Wood samples subjected to thermomechanical compaction were characterised by lower susceptibility to sanding measured on the basis of weight loss and lower surface roughness.

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43

Wang, Yue, Wei Wang, and Yao Chen. "Carnivorous Plant Algorithm and BP to Predict Optimum Bonding Strength of Heat-Treated Woods." Forests 14, no. 1 (December 27, 2022): 51. http://dx.doi.org/10.3390/f14010051.

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Анотація:

In this study, the CPA algorithm was used to optimize a BP neural network model to predict the bond strength and surface roughness of heat-treated wood. The neural network model was trained and optimized using MATLAB software. The results of the BP neural network, random forest algorithm, and optimized CPA-BP model were compared. The results show that the CPA-optimized BP neural network model has a better R2 compared to the conventional BP neural network model. After using the CPA-optimized BP neural network model, the R2 value increased by 8.1%, the MAPE value decreased by 3.74%, and the MAE value decreased by 33.91% in the prediction of the surface bond strength. The R2 values increased by 3.02% and 20.47%, respectively, in predicting the mean and maximum values of surface roughness. The results indicate that the model is reliable in predicting wood bond strength and wood surface roughness. Using this model to predict wood bond strength and surface roughness can also reduce the required experimental cost.

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44

Qabel, Faeze, Riehane Talaei, Saeedeh Saeedi, Raheb Ghorbani, and Nazila Ameli. "Comparative effect of three polishing systems on porcelain surface roughness after orthodontic bracket debonding and composite resin removal: An atomic force microscopy." APOS Trends in Orthodontics 9 (December 31, 2019): 223–29. http://dx.doi.org/10.25259/apos_7_2019.

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Анотація:

Purpose: Porcelain polishing after orthodontic bracket debonding and resin removal is imperative to eliminate surface roughness and minimize the risk of plaque accumulation, periodontal disease, and porcelain discoloration. This study aimed to assess the effect of three polishing systems on porcelain surface roughness after orthodontic bracket debonding. Materials and Methods: Thirty porcelain blocks were divided into three groups. Surface roughness of the samples was first measured using atomic force microscopy (AFM) and recorded as baseline. Orthodontic brackets were bonded to blocks by composite resin. After bracket debonding, resin remnants were removed by tungsten carbide bur. The blocks were then polished with Sof-Lex discs, Meisinger, and Jota porcelain polishing kit. Surface roughness was measured again using AFM. The Shapiro–Wilk test, one-way ANOVA, and Tukey’s post hoc test were used for data analysis through SPSS version 18.0. Level of significance was set at 5%. Results: The mean change in surface roughness after polishing with Jota kit (56.6 nm) was significantly greater than that compared to Sof-Lex discs (10.7 nm) (P = 0.003) and Meisinger kit (26.6 nm) (P = 0.024). The mean change in surface roughness was not significantly different between Sof-Lex and Meisinger groups. Surface roughness significantly increased in all three groups (P < 0.05). Conclusion: Meisinger polishing kit and Sof-Lex discs were not significantly different in terms of the resultant surface roughness. Thus, the conventional use of Sof-Lex discs seems to be more cost-effective due to their lower cost.

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45

Parkes, M. A., P. Coffey, and P. Connaughton. "The printing wood block collection of the Geological Survey of Ireland." Geological Curator 7, no. 4 (November 2000): 149–56. http://dx.doi.org/10.55468/gc445.

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Анотація:

The 19th century Memoirs of the Geological Survey of Ireland used standard printing technology of the period for illustrations, where a wood block was drawn upon and the wood carved away to provide a relief which transferred the ink to paper in the press as did the metal type for text characters. A collection of many hundreds of wood blocks has been 'rediscovered' within the Geological Survey of Ireland. The nature, condition and treatment of the wood block collection are described; the cataloguing has shown the majority of wood blocks for the 19th century memoir figures are still extant. Several wood blocks in different stages of development for unfinished memoirs illustrate the full process, and exemplify the artistry and skill required.

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46

Varasquim, Francisco Mateus Faria de Almeida, Manoel Cléber de Sampaio Alves, Marcos Tadeu Tiburcio Gonçalves, Luis Fernando Frezzatti Santiago, and Alexandre Jorge Duarte de Souza. "Influence of belt speed, grit sizes and pressure on the sanding of Eucalyptus grandis wood." CERNE 18, no. 2 (June 2012): 231–37. http://dx.doi.org/10.1590/s0104-77602012000200007.

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Анотація:

The sanding process is important to the quality of wood products. Sanding reduces imperfections in wood surfaces and it is important to the final product and application of paints or varnishes. There are few studies about sanding in the literature and finding out the relationship between the input parameters (i.e., species of wood, grit size, abrasive) on the output parameters (i.e., roughness, force, pressure) will help to improve this process. This study analyzed the influence of input parameters as belt speed (cutting speed), grit size and pressure on the output parameters as surface roughness, cutting force (sanding force) and power consumption on cross-grain sanding of Eucalyptus grandis wood. The tests were performed with 3 types of grit sizes (80, 100 and 120 grit), 3 belt speeds (10, 11 and 12 m/s) and 2 pressures (219.89 and 283.44 g/cm²). The surface roughness was analyzed based on roughness average (Ra). Sanding efforts were analyzed by cutting force and power consumption. It was found that the 100 grit size provided the lowest cutting force. It was observed that the belt speed, pressure and grit size influenced the surface roughness, cutting force and power consumption. The best surface finishes were obtained in tests with higher pressure.

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47

Dong, Huijun, Redžo Hasanagić, Leila Fathi, Mohsen Bahmani, Davor Kržišnik, Eli Keržič, and Miha Humar. "Selected Mechanical and Physical Properties of Thermally Modified Wood after Field Exposure Tests." Forests 14, no. 5 (May 12, 2023): 1006. http://dx.doi.org/10.3390/f14051006.

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This study aimed to evaluate the impact of thermal modification on the physical and mechanical properties of three different wood species from Bosnia and Herzegovina, namely beech wood (Fagus sylvatica L.), linden wood (Tilia cordata), and silver fir wood (Abies alba). The samples underwent thermal modification at five different temperatures (170 °C, 180 °C, 195 °C, 210 °C, and 220 °C) for varying durations (ranging from 78 to 276 min). After treatment, they were exposed to outdoor conditions for twelve months. The study examined the four-point bending strength, tensile force, color change, and surface quality of the modified and unmodified samples. The results showed that outdoor exposure negatively impacted the mechanical properties of the unmodified samples, especially in the linden wood which was 41% and the beech wood which was 42%. Additionally, outdoor exposure caused significant surface cracks in the thermally modified linden and beech wood. The study also found prominent color changes in the modified and unmodified samples during twelve months of exposure. The roughness of the samples was determined with a confocal laser scanning microscope, which showed that the roughness increased on both the axial and the longitudinal surfaces after weathering. The highest roughness for the fir wood was determined to be 15.6 µm. Overall, this study demonstrates the importance of wood modification and its impact on the use-value of wood products.

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48

Demir, Aydin, Evren Osman Cakiroglu, and Ismail Aydin. "Effects of CNC Processing Parameters on Surface Quality of Wood-Based Panels Used in Furniture Industry." Drvna industrija 73, no. 4 (November 15, 2022): 363–71. http://dx.doi.org/10.5552/drvind.2022.2109.

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Анотація:

The processing of wood-based panels such as plywood, particleboard and fiberboard, which are widely used in the furniture industry, with CNC (Computer Numerical Control) milling machines has been increasing recently. Even though CNC milling machines have many advantages for furniture producers, it is difficult to set process parameters to obtain the desired surface quality of the material. Therefore, it is necessary to determine the most suitable of these parameters for the surface quality of each wood-based panel. This study aimed to determine the effects of processing parameters on the surface quality of plywood, particleboard and medium density fiberboard (MDF) panels processed in CNC milling machines. Furthermore, the average surface roughness values of these panels were compared after CNC processing. Three spindle rotational frequencies (10.000, 14.000 and 18.000 rpm), three feed rates (5, 7, and 9 m/min) and two cutting tool diameters (2 and 5 mm) were selected as CNC processing parameters. To determine the surface quality of wood-based panels, the surface roughness measurements were performed according to DIN 4768 standard and three surface roughness parameters (Ra, Rmax and Rz) were determined. According to the results of this study, it can be concluded that the surface roughness values of wood-based panels decreased with increasing spindle rotational frequency and feed rate, while they increased with increasing cutting tool diameter. Among the wood-based panels used in this study, the lowest average roughness values were obtained for plywood samples.

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49

Zhang, Zhao, Arnaud Besserer, Christophe Rose, Nicolas Brosse, Vincent Terrasson, and Erwann Guénin. "Microwave-Assisted Synthesis of Pd Nanoparticles into Wood Block (Pd@wood) as Efficient Catalyst for 4-Nitrophenol and Cr(VI) Reduction." Nanomaterials 13, no. 17 (September 4, 2023): 2491. http://dx.doi.org/10.3390/nano13172491.

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Анотація:

Palladium (Pd) nanoparticle catalysis has attracted increasing attention due to its efficient catalytic activity and its wide application in environmental protection and chemical synthesis. In this work, Pd nanoparticles (about 71 nm) were synthesized in aqueous solution by microwave-assisted thermal synthesis and immobilized in beech wood blocks as Pd@wood catalysts. The wood blocks were first hydrothermally treated with 10% NaOH solution to improve the internal structure and increase their porosity, thereby providing favorable attachment sites for the formed Pd nanoparticles. The stable deposition of Pd nanoparticle clusters on the internal channels of the wood blocks can be clearly observed. In addition, the catalytic performance of the prepared Pd@wood was investigated through two model reactions: the reduction of 4-nitrophenol and Cr(VI). The Pd@wood catalyst showed 95.4 g−1 s−1 M−1 of normalized rate constant knorm and 2.03 min−1 of the TOF, respectively. Furthermore, Pd nanoparticles are integrated into the internal structure of wood blocks by microwave-assisted thermal synthesis, which is an effective method for wood functionalization. It benefits metal nanoparticle catalysis in the synthesis of fine chemicals as well as in industrial wastewater treatment.

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MAGOSS, ENDRE, RICHÁRD ROZS, and SÁNDOR TATAI. "EVALUATION OF WOOD SURFACE ROUGHNESS BY CONFOCAL MICROSCOPY." WOOD RESEARCH 67(6) 2022 67, no. 6 (December 13, 2022): 919–28. http://dx.doi.org/10.37763/wr.1336-4561/67.6.919928.

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The main aim of this study is to define the usability of the confocal scanning optical microscope (CSOM) to evaluate the wood surface roughness. Therefore, systematic investigation was carried out to define the influences of CSOM on the acquisition of 2D surface roughness parameters. Mahr Perthometer was applied to get reference data to estimatetheapplicability of the CSOM. Because wood roughness parameters measured with stylus and optical methods are not always comparable a calibration method was conducted on a metal calibration etalon. After the calibration process, the roughness profiles taken with the optical and stylus units were much closer to each other and only the optical Rpkparameter was definitely higher due to artificial peaks generated by the optical system. In order to eliminate this measuringfailure, the morphological filter option of the optical apparatus may be activated. Thesurface roughness parameters were measured on planed Scotch pine samples. The planed surface plains were produced with 0.2 mm parallel offset to investigate thestructural influence of the single cutting plains. The obtained results show that the average values for Ra, Rq, Rz, Rk, and Rvkare close to each other for both measuring systems, only theoptically measured Rpkvalues must be corrected. The standard deviations, however, are systematically slightly higher for optical system. This may be explained by the higher resolution of the optical system giving more fine profile details. The earlier developed and introduced dimensionless quantities, such as Abbott ratio, are also fully comparable for both systems provided that the optically measured Rpkvalues are also correct.

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