Composite wood products
Mohsen Saffari; mohammad reza ranjbar; mohammad ali ghavidel; abdollah hosseinzadeh
Abstract
AbstractThe aim of present study was to determine the relationship between ultrasonic wave velocity and mechanical properties of particleboard panels. For this purpose, homogenous and layering particleboards were made by 0/7 g/cm3 density and 16 mm thickness. After conditioning and preparing samples, ...
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AbstractThe aim of present study was to determine the relationship between ultrasonic wave velocity and mechanical properties of particleboard panels. For this purpose, homogenous and layering particleboards were made by 0/7 g/cm3 density and 16 mm thickness. After conditioning and preparing samples, ultrasonic wave velocity was measured in different directions of samples. Then modulus of elasticity, modulus of rupture and internal bonding of samples were measured by mechanical test machine. Result indicated that ultrasonic wave velocity of particleboard samples was higher in longitudinal direction than other directions. Relationship between ultrasonic wave velocity and mechanical properties was determined by linear correlation regression. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples.
Ghoncheh Rassam; Masoud Azadifar; Abolfazl Karegarfard; Faezeh Fazeli
Abstract
The purpose of this study was to examine the physical and mechanical properties of particleboard made using corn stalk. Mixtures of corn stalks and industrial wood particles at the ratios of 0:100, 30:70, 50:50, 70:30, urea-melamine formaldehyde resin at two levels of 10 and 12% (based on the dry weight ...
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The purpose of this study was to examine the physical and mechanical properties of particleboard made using corn stalk. Mixtures of corn stalks and industrial wood particles at the ratios of 0:100, 30:70, 50:50, 70:30, urea-melamine formaldehyde resin at two levels of 10 and 12% (based on the dry weight of the particles) and two press times of 5 and 6 minutes were used for the production of laboratory particleboard. Physical and mechanical properties including water absorption and thickness swelling after 24 hours soaking in water, modulus of rupture, modulus of elasticity and internal bonding were measured and the data were statistically analyzed. It was observed that the increase in corn stalk particles in the mixture resulted in reduction of water absorption, thickness swelling after 24- hours water soaking and the internal bonding. The modulus of rupture and elasticity of the boards were increased at higher ration of corn stalk particles. The higher dosage of resin and higher press time imposed significant effect on all properties boards and improving properties were reached. In general, comparing the produced boards properties with EN 312 requirements, the boards produced using 70% corn stalk particles, 12% urea-melamine formaldehyde and 6 minutes press time showed optimal properties.
Composite wood products
masoudreza habibi; Abdolrahman Hosseinzadeh; Hossein Hosseinkhani; Saeed Mahdavi
Abstract
In this study the effect of two variables, (resin content and press time) on properties of MDF was investigated. Levels of each variable was as follow: Resin content (8, 9.5, 11 percent) Press time (4, 5, 6 minutes). The statistical analysis proved that the effect of press time on MOE and MOR was significant. ...
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In this study the effect of two variables, (resin content and press time) on properties of MDF was investigated. Levels of each variable was as follow: Resin content (8, 9.5, 11 percent) Press time (4, 5, 6 minutes). The statistical analysis proved that the effect of press time on MOE and MOR was significant. MOE and MOR were the highest at press time of 6 minutes. According to Duncan's test, there aren’t any significant differences between MOE at press time of 5 and 6 minutes. Also the effect of resin content on MOE had significant differences. MOE was the highest at resin content of 11%. There aren’t any significant differences between MOE on resin content at 9.5% and 11% levels. The results showed that effects of press time and resin content had significant differences on IB. IB was the highest at press time of 6 minutes and resin content of 11%. There aren’t any significant differences between IB on resin content at 9.5% and 11%. The effects of press time and resin content had significant differences on thickness swelling after 2 hours. Thickness swelling was the lowest at press time of 6 minutes and resin content of 11%. According to the results of this study optimum combination for MDF production from baggasse includes resin content and press time of 9.5% and 5 minutes respectively.
Abdolrahman Hosseinzadeh; Nooshin Toghraie; Fardad Golbabaei; Nayeralsadat Sadraei
Abstract
In order to investigate The properties of wood eight-nineteen-years- old trees of Eucalyptus microtheca from De-hnow exprimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. From each tree, 10 cm thick cross-sectional discs at several ...
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In order to investigate The properties of wood eight-nineteen-years- old trees of Eucalyptus microtheca from De-hnow exprimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. From each tree, 10 cm thick cross-sectional discs at several different heights (3 metres intervals) were cut and together with remaining boles then transfered to the Alborz Research Center-Karaj for laboratory studies. The laboratory studies included determination of physical, anatomical and mechanical properties as well as chemical compositions of wood. The mechanical properties were evaluated on the ASTM samples for air-dry and green conditions. The following conclusions were drawn from this study:E. microtheca from one site in southern region of Iran has an average specific gravity of 0.804, fiber length of 0.811 mm, fiber diameter of 15.9 mm, lumen diameter of 5.7 mm, cell wall, thickness 5 mm, cellulose content of 44.47 percent.It was found that the mean values of modulus of rupture, modulus of elasticity and compression strength-parallel to grain tested at green condition were 72.50 MPa, 8066.6 MPa and 38.5 MPa and air-dried condition were 120.7 MPa, 12013.8 MPa and 69.80 MPa respectively.Data are also presented on other mechanical properties such as impact strength, nail withdrawal cleavage and et
Abdolrahman Hosseinzadeh; Habialah Arabtabar; Fardad Golbabaei; Hossein Familian; Nayeralsadat Sadraei; Masoudreza Habibi
Abstract
Eight-nineteen-year-old trees from Eucalytus steriaticalyx from Dehnow experimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. From each tree, 10 cm thick cross-sectional discs at several different heights (3 meters intervals) were ...
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Eight-nineteen-year-old trees from Eucalytus steriaticalyx from Dehnow experimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. From each tree, 10 cm thick cross-sectional discs at several different heights (3 meters intervals) were cut and together with remaining boles then transferred to the Alborz Research Center-Karaj for laboratory studies. The laboratory studies included determination of physical, anatomical and mechanical properties as well as chemical compositions of wood.The mechanical properties were evaluated on the ASTM samples for air-dry and green conditions. The following conclusions were drawn from this study:E. steriaticalyx from one site in southern region of Iran has an average specific gravity of 0.935, fiber length of 0.881 mm, fiber diameter of 16.063 m, lumen diameter of 4.465 m, cell wall thickness 5.789 m, cellulose content of 47.07 percent.It was found that the mean values of modulus of rupture, modulus of elasticity and compression strength-parallel to grain tested at green condition were 67.35 MPa, 8649 MPa and 35.36 MPa and air- condition were 117.53 MPa, 13397 MPa and 72.31 MPa respectively.Data are also presented on other mechanical properties such as impact strength, nail withdrawal cleavage and etc.
Physics and anatomy
Abdolrahman Hosseinzadeh; Hossein Familian; Kamyar Salehi; Abbas Fakhryan roghani; Fardad Golbabaei; Habibalah Arabtabar; Nayeralsadat Sadraei
Abstract
Eight-nineteen-year-old trees from Eucalyptus intertexta from Sarab bahman experimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. Form each tree, 10 cm. thick cross-sectional discs at several different heights (3 meters intervals) ...
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Eight-nineteen-year-old trees from Eucalyptus intertexta from Sarab bahman experimental Plantation located 160 Km. South west of Shiraz were selected randomly and fell two from each of the four blocks. Form each tree, 10 cm. thick cross-sectional discs at several different heights (3 meters intervals) were cut and together with remaining boles then transferred to the Alborz Research Center-Karaj for laboratory studies. The laboratory studies included determination of physical, anatomical and mechanical properties as well as chemical compositions of wood. The mechanical properties were evaluated on the ASTM methods for air-dry and green conditions. The following conclusions were drawn from this study:E. intertexta from one site in southern region of Iran has an average specific gravity of 0.86, fiber length of 0.71 mm, fiber diameter of 25.26 mm, lumen diameter of 4.04 mm, cell wall thickness 5.62 mm, cellulose content of 45.95; lignin 28.2; extractives soluble in alcohol - Banzen 4.28 and ash 0.62 percent.It was found that the mean values of modulus of rupture, modulus of elasticity and compression strength-parallel to grain tested at green condition were 74.21 MPa, 8454 MPa and 38.52 MPa and air-dried condition were 123.47 MPa, 14667 MPa and 77.99 MPa respectively. Data are also presented on other mechanical properties such as impact strength, nail withdrawal cleavage and etc.
Abolfazl Kargarfard; Ali akbar Enayati; Ahmad Jahan latibari; Abdolrahman Hosseinzadeh; Amir Nourbakhsh
Composite wood products
Ahmad Jahan latibari; Abdolrahman Hosseinzadeh; Taghi Tabarsa
Abstract
In this investigation, the effect of mat moisture content, press temperature and time on polymerization reaction of urea-formaldehyde (UF) resin and the strength of UF bonded hornbeam particleboard is studied. Variation of three variables is as followed:
-mat moisture content; 10, 13 and 16% (Based ...
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In this investigation, the effect of mat moisture content, press temperature and time on polymerization reaction of urea-formaldehyde (UF) resin and the strength of UF bonded hornbeam particleboard is studied. Variation of three variables is as followed:
-mat moisture content; 10, 13 and 16% (Based on oven dry weight of wood)
-Press temperature; 150, 170 and 190 ᵒC
-Press time; 4, 6, and 8 min.
Fore boards were manufactured for each combination of variables. Modulus of rupture (MOR), modulus of elasticity (MOE), Internal bond (IB), water absorption (Wa2 and Wa24) and thickness swelling (Ts2 and Ts24) after 2 and 24 hours immersion in water were determined according to ASTM 1037 standard. All data was analyzed using factorial design. The effect of mat moisture content on MOR was not statically different, but its effect on MOE was statistically different at 5% significance level, and increasing the mat moisture content from 10 to 16% bout MOR & MOE. Highest level of MOE (4262 MPa) corresponds to board pressed at 16% mat moisture content. On the contrary, mat moisture content decreased the IB and lowest value of IB ( 1.447 MPa) corresponds to boards pressed at 16% mat moisture content. The effect of mat moisture content on IB was statistically different at 1% significance level. Increasing mat moisture content decreased water absorption and increased thickness swelling. Lowest Wa2 & Wa24 was observed on boards pressed at 16% mat moisture content (67.35% & 86.78% respectively) and lowest Ts2 & Ts24 was observed on boards pressed at 10% mat moisture content (21.89% & 27.32% respectively). There force for the production of suitable boards, ma moisture content must be kept at 10-13% range.
Composite wood products
Ahmad Jahan latibari; Abdolrahman Hosseinzadeh; Amir Nourbakhsh; Abolfazl Kargarfard; Fardad Golbabaei
Abstract
The influence of production variable such as residues moisture content at time of chipping or flaking, hardner and press time on properties of particleboard from date palm residues is investigated. Each variable was investigated at three different levels and a total of 24 combinations of variables were ...
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The influence of production variable such as residues moisture content at time of chipping or flaking, hardner and press time on properties of particleboard from date palm residues is investigated. Each variable was investigated at three different levels and a total of 24 combinations of variables were studied. The results of this investigation indicate that:
- Residues moisture content at the time of chipping or flaking affects both physical and mechanical properties of boards. MOR and MOE of board made from flakes produced by dry chipping and either wet or dry flaking was higher than others and its dimensional stability was better.
Chipping or flaking moisture did not affect IB significantly.
- Hardner consumption did not significantly influence the properties, but increasing hardner consumption to 3 percent of resin content (solid basis) improved board properties.
- Press time also did not influence board properties and for the production of 15 mm. boards, either 5 or 6 minutes press time can be used.
-For the production of boards to satisfy DIN requirement, following variable combination can be utilized: dry chipping - wet flaking, 3 percent hardner and 6 minutes press time.
