Saman Ghahri; Reza Hajihassani; Kamyar Salehi; Fardad Golbabaei
Abstract
In this study, the mechanical properties of kenaf cement composite were investigated using different amounts of kenaf particles (mixture of kenaf core and bark and kenaf core particles). Kenaf-cement composites were manufactured at different levels (10, 15 and 20%) of different kenaf particles. Also, ...
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In this study, the mechanical properties of kenaf cement composite were investigated using different amounts of kenaf particles (mixture of kenaf core and bark and kenaf core particles). Kenaf-cement composites were manufactured at different levels (10, 15 and 20%) of different kenaf particles. Also, Portland cement and calcium chloride (as cement accelerating additive) were used in this research. Calcium chloride and water were mixed well and then kenaf particles were added to the mixture. At next stage, cement was added to the prepared mixture and all component were mixed well. Prepared mixture was molded to the wooden mold and kenaf cement composites were produced. The results obtained from mechanical evaluation of kenaf-cement composites showed the highest bending strength in 10% kenaf bark-cement composites. Also results revealed that highest modulus of elasticity of 10% kenaf core-cement products were obtained. The results of this research revealed the potential of kenaf particles as reinforcement in cement composite production.
Reza Hajihassani; Saman Ghahri; Kamyar Salehi; Fardad Golbabaei; seyedeh masoomeh
Abstract
Abstract In the current research, surface properties and failure modes of modified poplar wood (Populus deltoides) by hygrothermal treatment were evaluated. For this aim, the effect of variable factors included hygrothermal temperature (three levels: 130, 150 and 170°C) and holding time (two levels: ...
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Abstract In the current research, surface properties and failure modes of modified poplar wood (Populus deltoides) by hygrothermal treatment were evaluated. For this aim, the effect of variable factors included hygrothermal temperature (three levels: 130, 150 and 170°C) and holding time (two levels: 20 and 40 minutes) on poplar wood specimens properties (contact angle and surface roughness) prior to and after planning were investigated. The surface characteristics and failure modes were evaluated for both treated and untreated wood specimens. The results revealed that surface roughness of poplar wood was enhanced due to the hygrothermal treatment in both states of before and after planning. It was also found that the hygrothermal treatment decreased contact angle of distilled water. The bending strength of specimens was reduced by hygrothermal treatment. According to the results, failure modes of hygrothermally treated specimens were simple and compression types in bending strength test. Keywords: Surface roughness, contact angle, bending strength, failure mode
Abolfazl Kargarfard; Reza Haji hassani
Abstract
The aim of this investigation was concentrated on the possibilty of untilizing corn cops residues in the production of particleboard. Two press temperatures of 170 and 180 oC, and four ratios of corn cop/poplar wood particles (100/0, 75/25, 50/50 and 25/75) in the corn layer of the boards and 100% poplar ...
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The aim of this investigation was concentrated on the possibilty of untilizing corn cops residues in the production of particleboard. Two press temperatures of 170 and 180 oC, and four ratios of corn cop/poplar wood particles (100/0, 75/25, 50/50 and 25/75) in the corn layer of the boards and 100% poplar wood particles in the surface layer were used. A combination of 16 treatments were reached and three laboratory boards for each treatment were made. Physical and mechanical properties of the boards were measured and statistically analyzed. The grouping of the averages were based on duncan multiple range test. The results indicated that the influence of the press temperature on both modulus of rupture and modulus of elasticity was statistically significante and boards produced applying 170 oC reached higher values. As the ratio of the corn cop particles in the particle mixture in core layer increased, both modulus of rupture and internal bonding deteriorated and the highest value were measured at 50/50 ratio of the particle in the core layer. The Boards which produced applying higher press temperature exhibited hgiher rate of thickness swelling . Lower ratios of the corn cop particle in the mixture of particles in the core layer improved the properties of the boards. So that the ratio of 50/50/ and 25/75 produced lower thickness swelling. The results of this research revealed that eventhough boards produced using corn cop particles did not produce comparable properties to the boards based on poplar particles, but it can be concluded that if 50/50 ratio of particles, press temperature of 170 oC is used for board making, the mechanical properties of the produced boards will meet the requirement of DIN specifications.
Composite wood products
Fardad Golbabaei; Kamyar Salehi; Reza Hajihassani
Abstract
In this study, the composition of bagasse composite was investigated using different amounts of bagasse particles. Bagasse and cement particles are manufactured at levels (5, 10 and 15%) and percentage of calcium chloride as cement accelerating additive at two levels (3 and 2%) based on cement dry weight. ...
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In this study, the composition of bagasse composite was investigated using different amounts of bagasse particles. Bagasse and cement particles are manufactured at levels (5, 10 and 15%) and percentage of calcium chloride as cement accelerating additive at two levels (3 and 2%) based on cement dry weight. Then, the mixture was poured into a mold measuring 15 8 18 8 8 cm and the excess water was removed from the bottom of the mold and initially weighed 10 kg on the specimens. The specimens were removed from the mold after 48 hours and kept in a glass saturated room at 90% humidity for 14 days and then finally dried in a laboratory environment. The bending strength and physical properties tests were performed on the specimens. The results showed that bagasse particles had a significant effect on bending strength and other physical properties. The bending strength was highest in boards made with 10% bagasse particles.
Composite wood products
Laya jamali rad; saeed Narooei
Abstract
The purpose of this study was to investigate the possibility of using tobacco stalk and industrial wood particles in particleboard industry as a waste material that is not consumed and discarded and has a low price, followed by a reduction in production costs from the way of choosing this raw material ...
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The purpose of this study was to investigate the possibility of using tobacco stalk and industrial wood particles in particleboard industry as a waste material that is not consumed and discarded and has a low price, followed by a reduction in production costs from the way of choosing this raw material was of low value. For this purpose, the particles of tobacco stalk and industrial wood particles with different ratios of 0:100, 30:70 and 60:40, using the amount of adhesive used 12% and 14% (based on the dry weight of the wood chips) and the press time of 5 minutes for the construction of the board was considered. Physical and mechanical properties including thickness swelling after 2 and 24 hours immersion in water and bending strength (MOR), modulus of elasticity (MOE) and internal bonding (IB) were measured and all data were statistically analyzed. According to the results of this study, the increase in tobacco stalk particles resulted in increased thickness swelling after 2 and 24 hours immersion in water and reduced bending strength, modulus of elasticity and internal bonding, but all boards had a European standard (EN). Increasing the amount of resin also had a significant effect on all the properties of the boards and improved the properties. In a general conclusion and by comparing the properties of the boards produced with the European standard (EN), showed that using 60% tobacco stalk and 12% urea formaldehyde resin can be produced particleboard with the desired properties. This is a positive result of using tobacco stalk as a type of agricultural residue and, consequently, the prevention of environmental pollution caused by the burning of these compounds.
Composite wood products
Masoudreza Habibi
Abstract
The purpose of this study was to use of Hemp stalks in particleboard production. Mixtures of Hemp stalk and Eucalyptus wood at the ratios of 0:100, 50:50, 100:0 were used. Also two resin content of 8 and 10% (based on oven dry particle) and 2 press times of 3 and 4 minutes were employed for the production ...
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The purpose of this study was to use of Hemp stalks in particleboard production. Mixtures of Hemp stalk and Eucalyptus wood at the ratios of 0:100, 50:50, 100:0 were used. Also two resin content of 8 and 10% (based on oven dry particle) and 2 press times of 3 and 4 minutes were employed for the production of laboratory particleboard. Physical and mechanical properties including thickness swelling after 2 and 24 hours soaking in water, modulus of rapture, modulus of elasticity and internal bonding were measured data were statistically analyzed. It was observed that the increase in Hemp stalk particles in the mixture resulted in increasing of bending properties (bending strength and modulus of elasticity) and thickness swelling after 2 and 24 hours water soaking. Also the results showed that increase in Hemp stalk particles in the mixture resulted in reduction of internal bonding. As expected, physical and mechanical properties of particleboard improved with increasing resin content. Modulus of elasticity and thickness swelling after 24 hours water soaking were improved with increasing of press time. In general, comparing the produced board mechanical properties with standard of Iran requirements, the board produced using 100% and 50% Hemp stalk, 8% resin content and 3 minutes press time showed that optimal properties. Although the physical properties of the boards did not meet the standard values, the reason for this could not be due to the lack of use of paraffin.
Composite wood products
Laya Jamalirad; Fereshteh Kor; Farshid Faraji; Sahab Hedjazi
Abstract
In this research, the manufacture of particleboard using lignocellulosic residues including wheat straw and tobacco stalks mixed with industrial wood chips were studied. The variable factors included the mixture of wheat straw and tobacco stalks with industrial wood chips in four levels 0/100, 20/80, ...
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In this research, the manufacture of particleboard using lignocellulosic residues including wheat straw and tobacco stalks mixed with industrial wood chips were studied. The variable factors included the mixture of wheat straw and tobacco stalks with industrial wood chips in four levels 0/100, 20/80, 40/60 and 60/40 (In any combination, according to the desired levels, tobacco stalks and wheat straw were used equally) and the amount of urea formaldehyde resin was at two levels 12 and 14% of the dry weight of the wood chips. The results showed that by increasing the mixture of wheat straw and tobacco stalk up to 60 percent, the physical and mechanical properties of the boards decreased significantly. But increasing the amount of adhesive consumption up to 14 percent had a positive impact on the physical and mechanical properties of the boards and improved internal bonding, bending strength and modulus of elasticity and dimensional stability of the boards. It means that by increasing the use of this type of wastes up to 40 percent with an increase in the amount of UF adhesive up to 14% can be produced the boards with the mechanical properties at standard level.
amir lashgari; Payam Khodayari; Seid Ali Mohammadi
Abstract
In this research the effect of nail′s length on three different values (32,42,48 mm)the nail number (2 and 3)and the kind of of particleboard and MDF on tensile strength and bending moment has been analyzed ,The member dimension of of 10*15*1.6 cm.have been elected for making of L –type ...
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In this research the effect of nail′s length on three different values (32,42,48 mm)the nail number (2 and 3)and the kind of of particleboard and MDF on tensile strength and bending moment has been analyzed ,The member dimension of of 10*15*1.6 cm.have been elected for making of L –type joint. The junction have not used out of any adhesive as an adjuvant. From combination of this variable factors and examination of any strength some 24 samples have created,that due to the 4 iterations,96 specimens of L shaped joints have been coustructed totally.the bending and tensile strength of produced junction has been measured by mechanical test machine.based on captured results the interaction of constituents of,nail penetration length,nails number and members nature on joint strenght weren′t significant in front of tensile and bending.this research indicated that the junctions with the penetration length of 48 mm,the most amount of nail(three nails)on MDF member elements,have the greatest strength against bending strength,and the link with penetration length of 42mm alone with the most amount of nail(3 nails)on MDF have the greatest strength against tensile,as copared with each other.
amir lashgari; Mohssen Ahmadi
Abstract
Aim of this study were to examine the effects of pin diameter (6, 8 and 10 millimeter), the pins interval ( 30,50 and 70 millimeter), wooden pin penetration depth (2d,3d and 4d D=Diameter of pin) and the shape of H joint on bending strength of the joint. In order to make the H joints, the dimension of ...
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Aim of this study were to examine the effects of pin diameter (6, 8 and 10 millimeter), the pins interval ( 30,50 and 70 millimeter), wooden pin penetration depth (2d,3d and 4d D=Diameter of pin) and the shape of H joint on bending strength of the joint. In order to make the H joints, the dimension of the middle member was selected as 200x125x16 millimeter and the dimension of the side members were selected as 250x125x16 millimeter. MDF was used to make the joints. The wooden pin used in the present research was made from hornbeam (Carpinus betulus) which is common pin in the market. PVA glue was used to make pin joints. Twenty seven treatments were obtained out of various combinations of the variables and considering four replication for each treatment, 108 H-shaped samples were prepared. The bending strength of the joints was measured. The results from mechanical test indicated that for each pin penetration depths in H joint, increasing the distance between pins, the bending strength decreased. Maximum bending strength was related to the pins having diameter of 10 millimeter. In 4d penetration depth, for each three diameters of 6, 8 and 10 millimeter, the maximum bending strength was reached on 30 millimeter intervals. The minimum bending strength for the pin having 6 millimeter diameter was obtained in the interval of 10 millimeter. The same results were obtained for the 2d and 3d penetration depths.
amir lashgari; Peyman Sinambari
Abstract
Effects of screw length (2, 2.5,3 inch), wood species (beech, alder, white spruce), and two screw interval (2, 2/5 cm) on bending strength of the T-type joints were investigated. In order to fabricate the T –shaped joints, dimensions of the parts were determined as 15*5/5*2/5 cm. From the ...
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Effects of screw length (2, 2.5,3 inch), wood species (beech, alder, white spruce), and two screw interval (2, 2/5 cm) on bending strength of the T-type joints were investigated. In order to fabricate the T –shaped joints, dimensions of the parts were determined as 15*5/5*2/5 cm. From the above variables, 18 combinations were reached. Four replications, and a total of 72 specimens were made and the mechanical strength of the specimens were measured by mechanical testing machine. Results indicated that the beech joints with 3-inch length screws had the highest bending strength, while the lowest bending strength was observed in spruce wood with 2-inch length screws. The study revealed statistically significant differences between the wood species, while there were not any difference between screw interval and bending resistance.
Mysam Abdolali sarbandi; Vahid Safdari; Sayed javad Sepidedam; Esmaeil Ganjyan
Abstract
In this research, the properties of cement fiberboard produced using different contents of nano-silica and bleached bagasse fibers were evaluated. Different ratios of bagasse fibers, cement and nano-silica were blended using an electrical blender. The mixture was then poured into a mould (15x18x18 ...
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In this research, the properties of cement fiberboard produced using different contents of nano-silica and bleached bagasse fibers were evaluated. Different ratios of bagasse fibers, cement and nano-silica were blended using an electrical blender. The mixture was then poured into a mould (15x18x18 cm dimension). The produced mould samples were matured for 14 days at room temperature and high moisture content (100%) and after maturing, the bending strength and physical properties of boards were measured. Results showed that both materials (naosilica and bagasse fibers) changed the bending and physical properties of the final boards. The bending strength of samples increased with the increase in nano-silica up to 1% and exceeding 1% decreased this property. It is because high content of silica (more than 1%) results in aggregate of nano-silica and cement and micro cracks occurred in samples. Also the increase in bagasse fiber up to 4% increased of bending strength of boards and more bagasse fibers decreased the bending strength. It is because high bagasse fibers cannot distribute in the cement matrix and fiber bundles reduced the bending strength. However, as the nano-silica and bagasse fibers content increase, the water and moisture absorption as well as thickness swelling increases, whereas density decreases.
Aliakbar Ramtin; Behnaz Dadkhahi tehrani; Kazemi Dossthoseini
Abstract
In this study, effects of press temperature and press time on the physical and mechanical properties on the OSB has made from Aspen were investigated. Two levels of press temperature 175ºC and 185ºC and two levels of press time 5 min and 6 min were applied as variables for manufacturing boards. ...
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In this study, effects of press temperature and press time on the physical and mechanical properties on the OSB has made from Aspen were investigated. Two levels of press temperature 175ºC and 185ºC and two levels of press time 5 min and 6 min were applied as variables for manufacturing boards. Mechanical and physical properties such as bending strength, internal bond, water absorption and thickness swelling were measured. results showed that, increase in press temperature and press time causes significant increase on bending strength, internal bond, water absorption and thickness swelling. The best boards were made of press temperature of 185ºC and press time 5 minutes.
Composite wood products
Saeid Kazemi najafi; Ali Shalbafan; Majid Charmahali
Abstract
Density profile of three types of medium density fiberboard (MDF) panels used in Iran market was studied through direct method and gradually removing of layer. Modulus of elasticity, bending strength, internal bond, water absorption and thickness swelling were also determined. The results show that the ...
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Density profile of three types of medium density fiberboard (MDF) panels used in Iran market was studied through direct method and gradually removing of layer. Modulus of elasticity, bending strength, internal bond, water absorption and thickness swelling were also determined. The results show that the shape of density profiles in all types of panels is nearly symmetric and normal, but the profil density in one was deeper, so it showed higher modulus elasticity and bending strength. No significant difference in internal bond was observed between different types of panels.
Pulp and paper
asghar tarmian; Kazem Doosthosseini; Seeyed Ahmad Mirshokraie; Mohammadmehdi Faezi poor
Abstract
Beneficial utilization of large quantity of paper sludge from Mazandaran Wood & Paper Industry in particleboard manufacturing has been studied. Single-layer and three-layer particleboard (paper sludge as a surface layer) were produced. Urea-formaldehyde resin at two levels of 10 and 12 percent and ...
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Beneficial utilization of large quantity of paper sludge from Mazandaran Wood & Paper Industry in particleboard manufacturing has been studied. Single-layer and three-layer particleboard (paper sludge as a surface layer) were produced. Urea-formaldehyde resin at two levels of 10 and 12 percent and paper sludge content at 4 levels, 0, 15, 30 and 45 percent were studied. Other factors such as press temperature (160oC), press time (6minutes), mat moisture (12%), board density (0.75g/cm3) and etc were constant factors. Mechanical and physical properties including bending strength, shear strength, thickness swelling and water absorption after 2 and 24 hours immersion were evaluated. The results indicated that application of paper sludge reduced mechanical properties and improved thickness swelling .The particleboard produced with 15%paper sludge had the least water absorption, but by using more paper sludge, water absorption increased. Single-layer particleboard had higher bending strength. However, there was no significant different in shear strength between single and three layer particleboard. Three-layer particleboard showed lower thickness swelling.
Composite wood products
Hossein Hosseinkhani; Abdolrahman Hosseinzadeh; Fardad Golbabaei; Amir Nourbakhsh; Nayeralsadat Sadraei; masoudreza Habibi
Abstract
In this study, the effect of board type, press time and resin content on the strength of particleboard have been evaluated. The boards made for this study contained bagasse and logging residues of Eucalyptus wood particles at a 50 to 50 ratio and employed Urea formaldehyde (UF) resin as the binder. Variable ...
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In this study, the effect of board type, press time and resin content on the strength of particleboard have been evaluated. The boards made for this study contained bagasse and logging residues of Eucalyptus wood particles at a 50 to 50 ratio and employed Urea formaldehyde (UF) resin as the binder. Variable factors are as follows:- type of board; single layer, three layer- press time; 5 , 6 , 7 , minutes- resin content; 9 , 10 , 11 percentThree boards' were manufactured for each combination of variables. Samples of all the boards made were tested by the methods described in DIN 68763 standard to obtain mean values of bending strength, and internal bond strength (LB). In addition samples of each type of board were tested for thickness swelling after immersion in water for 2 hours and 24 hours respectively.The results of this study show clearly that three layer particleboard has significantly higher bending strength than single layer, but single layer boards have better properties from the physical aspect.
Increasing the content of U.F resin from 9 per cent to 10 per cent was found to reduce the thickness swelling, and tended to improve the strength properties of the board, in both single layer and three layer boards. Press time has significant effect on bending strength and I.B Highest MOR and MOE were observed on three layer board pressed for 7 minutes.
