Investigation of selected properties of the black elder wood (Sambucus nigra L.)

2021 ◽  
Vol 116 ◽  
pp. 28-38
Author(s):  
Paweł Kozakiewicz ◽  
Marcin Dadon ◽  
Monika Marchwicka

Investigation of selected properties of the black elder wood (Sambucus nigra L.). The work has defined the selected chemical, physical and mechanical properties of the black elder wood, such as content of non-structural substances, shrinkage and density, speed of sound propagation, dynamic modulus of elasticity, acoustic resistance and sound attenuation, modulus of elasticity, bending strength, compressive strength, Brinell hardness, cold and hot-water extractives content and pH of hot-water extract. The black elder wood is hard and moderately shrinking. Mechanical properties are reduced by going from the pith to the perimeter, which is most likely affected by the increasing twist of the fibres. The distance from the pith also affects the acoustic properties and the size of the shrinkage, while the density remains constant.

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1750 ◽  
Author(s):  
Radosław Mirski ◽  
Pavlo Bekhta ◽  
Dorota Dziurka

This study examined the effects of selected types of thermoplastics on the physical and mechanical properties of polymer-triticale boards. The investigated thermoplastics differed in their type (polypropylene (PP), polyethylene (PE), polystyrene (PS)), form (granulate, agglomerate) and origin (native, recycled). The resulting five-ply boards contained layers made from different materials (straw or pine wood) and featured different moisture contents (2%, 25%, and 7% for the face, middle, and core layers, respectively). Thermoplastics were added only to two external layers, where they substituted 30% of straw particles. This study demonstrated that, irrespective of their type, thermoplastics added to the face layers most favorably reduced the hydrophobic properties of the boards, i.e., thickness, swelling, and V100, by nearly 20%. The bending strength and modulus of elasticity were about 10% lower in the experimental boards than in the reference ones, but still within the limits set out in standard for P7 boards (20 N/mm2 according to EN 312).


2019 ◽  
Vol 70 (3) ◽  
pp. 221-228
Author(s):  
Abdullah Istek ◽  
Ismail Ozlusoylu

In this study, the effect of mat moisture content on the physical and mechanical properties of particleboard was investigated. The experimental boards were produced by using 40 % softwood, 45 % hardwood chips, and 15 % sawdust. The formaldehyde resin/adhesive was used in three-layers (bottom-top layer 12 %, core layer 8 %). Multi-opening press was used during manufacturing the experimental particleboards. The physical and mechanical properties of boards obtained were identified according to the TS-EN standards. The optimum core layer moisture content was determined as 6 % and 7 % according to the results, whereas the moisture content of bottom and top layers was 14 %. Under these moisture content conditions, the bending strength was found to be 13.3 N/mm², the modulus of elasticity in bending 2466 N/mm², and internal bonding strength 0.44 N/mm². The optimum bottom-top layer moisture content was determined to be between 13 % and 15 % and 6.5 % for the core layer.


PERENNIAL ◽  
2008 ◽  
Vol 4 (1) ◽  
pp. 6
Author(s):  
Apri Heri Iswanto ◽  
Zahrial Coto ◽  
Kurniawansyah Effendy

The objective of this research is to research the effect of particle soaking to physical and mechanical properties particleboard that resulted. The best result of particleboard is particleboard with treatment of hot water soaking. From this result obtained average of physical properties of particleboard (i.e. density, moisture content, water absorption, and thickness swelling) are 0.7 g/cm3; 9.58%; 52.27%; 10.05%. While the result average of mechanical properties of particleboard (i.e. Modulus of Rupture, Modulus of Elasticity, Internal Bond and Screw Holding Power) are 118.79 kg/cm2; 8.909 kg/cm2; 1.85 kg/cm2; 28.40 kg. Key words: Soaking, bagasse, particleboard, physical and mechanical properties References


2021 ◽  
Vol 1 (3) ◽  
pp. 28-35
Author(s):  
Arkadii N. Avdeev ◽  
Elena L. Sosnovskaia ◽  
Aleksandr Iu. Bolotnev

Introduction. In exploration, construction, and mining operations it is necessary to assess the physical and mechanical properties of rocks. However, laboratory rock tests are expensive, time-consuming, and require a large number of quality rock samples. There is a problem of rapid evaluation of physical and mechanical properties by indirect, non-destructive methods. The problem is considered on the example of one of the basic properties, the strength coefficient according to Protodiakonov's scale. Research methodology included the analysis of the main indirect methods of determining the strength coefficient based on strength, elastic and acoustic properties of rocks on the grounds of statistical empirical relationships of V. V. Rzhevskii, G. Ia. Novik, L. I. Baron; K. L. Ter-Mikaelian, A. I. Beron, and M. M. Protodiakonov. The most promising methods based on non-destructive laboratory tests of modulus of elasticity and longitudinal wave velocity are selected. Results and conclusions. The strength coefficient was calculated by several methods on the example of siliceous sandstones, selected from the exploration well of the gas-bearing field. The results were compared with each other and with cadastral references and materials. The most optimal for calculations were the dependences of V. V. Rzhevskii, G. Ia. Novik, and L. I. Baron when evaluating the strength coefficient by the modulus of elasticity, and the dependences of A. I. Beron and L. I. Baron when calculating based on acoustic characteristics.


2012 ◽  
Vol 42 (5) ◽  
pp. 831-840 ◽  
Author(s):  
C. Pollet ◽  
C. Verheyen ◽  
J. Hébert ◽  
B. Jourez

The objective of this study was to characterize black locust ( Robinia pseudoacacia L.) wood on the basis of its physical and mechanical properties. The results are compared with those reported in the literature for English oak ( Quercus robur L.), teak ( Tectona grandis L. f.), and afzelia ( Afzelia sp.), since black locust is likely to be used for the same purposes as the former species. The variations between sites, trees, and radial positions in the trunk were also studied. The physical and mechanical properties of black locust wood were evaluated on clear wood specimens taken from 27 trees distributed over five sites in Wallonia (Belgium) according to Belgian and French standards. Most of the black locust’s mechanical properties are higher than those of oak and teak. The black locust is classified as a “mid-heavy” (734 kg·m–3) and “half-hard” (5.22) wood type with very high resilience (17.2 J·cm–2), modulus of elasticity (15 700 MPa), and tensile strength in static bending (138 MPa). Its resilience is exceptional, higher than that of teak and afzelia, while its modulus of elasticity and bending strength, which surpass those of teak, are comparable with those of afzelia. Black locust shows high total volumetric shrinkage (16%), placing it in the “nervous” class, average tangential (8.8%) and radial shrinkage (5.5%) as well as average axial compressive (63 MPa) and splitting strength (17.8 N·mm–1). No technological incompatibilities would prevent the use of this wood for many value-added purposes (floor, deck, exterior woodwork, and furniture); however, significant shrinkage makes it necessary to condition the wood to its service moisture.


2019 ◽  
Vol 8 (3) ◽  
pp. 6484-6487

Possibilities for use of banana fiber and currency notes thermally modified groups were evaluated for the production of plywood boards in industrial conditions. Formats of groups were treated at temperatures of 190 °C, 200 °C, 210 °C, and 215 °C for each 9 h to making the pulp process. By combining the treated and non-treated formats of veneer in types of board groups, thirteen different types of board were made. Analysis showed that the examined physical and mechanical properties were influenced by both the type of construction and the applied thermal treatment. Boards composed only of thermally modified group achieved the best results regarding moisture absorption and dimensional stability, and boards composed of the combined currency notes and banana fiber had better mechanical properties. As per the analysis of plywood board when used banana fiber used in pulp of plywood board is suitable at190 °C temperature rather than 215 °C temperature with comparing the other types of board. 25 °C temperature is less requires for control group board. We can consume cost of heat which is used in this process and getting the hard quality of plywood. At 215 °C temperature of processing cost of heat is 10% of plywood cost and when at 190°C of processing the cost of heat is 9.06% of plywood cost so that we can consume 0.94% cost of heat. Moisture content of temperature conditioned boards of control group is 9.01% density of conditioned boards 436.36 kg/m3 . Highest bending strength and modulus of elasticity of boards is 48.07MPa and 6078 MPa in longitudinal direction and bending strength and modulus of elasticity of boards in cross-section 28.40MPa and 2027 MPa.


BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 4693-4703
Author(s):  
Alperen Kaymakci ◽  
Bahadır Çağrı Bayram

Effects of the heat treatment parameters were evaluated relative to some physical and mechanical properties of poplar wood (Populus alba L.) with use of two of the prominent multi criteria decision-making (MCDM) techniques: Entropy and The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). To meet this objective, the test samples were heat-treated at 120, 150, 180, and 210 °C for 2 and 4 h in a laboratory-scale oven. With increasing temperature and duration, the shrinkage and swelling ratios of heat-treated samples were improved. However, the bending strength, modulus of elasticity, and compression strength generally decreased with increasing process temperature and duration. According to (MCDM) analyses, thermal modification definitely improved the physical properties of wood up to a point. Bending strength was found to be the most important determinant of heat treatment success. The other determinants were identified as swelling, compression strength, shrinkage, and modulus of elasticity, respectively. Also, the best results were obtained at 120 °C for 2 h. In general, heat treatment above 150 °C or 4 h is not recommended.


2012 ◽  
Vol 51 (No. 2) ◽  
pp. 76-94
Author(s):  
J. Hrázský ◽  
P. Král

The paper summarizes results of an institutional research aimed at assessing the bending strength and modulus of elasticity in bending of exterior foiled combined and all-beech plywoods in relation to their construction. A relationship was studied of the plywood construction and selected physical and mechanical properties. In studied sheets, moisture, density, bending strength and modulus of elasticity were analysed along and across the grain of the upper veneer. All measurements were carried out in water-resistant plywoods with surface treatment with a phenolformaldehyde foil 8, 10, 12 and 15 mm thick in combined plywoods and 10, 12, 15 and 18 mm thick in all-beech plywoods. The construction of plywoods significantly influences their quality that is determined particularly by the bending strength and modulus of elasticity. Using regression analysis relationships were demonstrated particularly that with the increasing moisture content of plywoods the bending strength decreased and with the increasing density the bending strength and modulus of elasticity increased. The same trend was also proved in connection with the increasing number of veneers of plywood sheets. Using correlation analysis, combinations of interrelationships of the given properties were statistically tested.


2014 ◽  
Vol 775-776 ◽  
pp. 599-603 ◽  
Author(s):  
Jaime Domingos Teixeira ◽  
Manuel Alfredo Pereira ◽  
Lourival Boehs ◽  
Cristina Siligardi ◽  
Vicente Cantavella ◽  
...  

Physical and mechanical properties of a glass-ceramic belonging to the LZS (Li2O-SiO2-ZrO2) system were investigated by dilatometric analysis, differential thermal analysis, X-ray diffraction and measurements of density, hardness, bending strength, modulus of elasticity and fracture toughness. The obtained glass-ceramics showed ZrSiO4 and Li2Si2O5 as main crystalline phases, relative densities between 84 and 99%, maximum hardness, bending strength, modulus of elasticity and toughness of 8±0.5 GPa, 214±20 MPa, 115±0.42 GPa and 3.65±0.21 MPa.m1/2, respectively.


2010 ◽  
Vol 105-106 ◽  
pp. 549-552
Author(s):  
Jie Liu ◽  
Long Quan Shao ◽  
Yuan Fu Yi ◽  
Bin Deng ◽  
Wei Wei Zhang ◽  
...  

Objective: To study the effects of presintering temperature and temperature rise speed on the physical and mechanical properties of alumina-glass-composite (AGC). Methods: AGC was prepared respectively under the condition that presintered at 1400°C and 1450°C as well as two kind of temperature rise speed. The properties were measured, including density, thermal expansion coefficient, three-point bending strength, fracture toughness, modulus of elasticity and Vicker’s hardness of AGC. Results: With the increasing of presentering temperature and the temperature rise speed, density of AGC decreased, bending strength, fracture toughness, modulus of elasticity increased markedly. There was no difference between three-point bending strength and fracture toughness of AGC that was made by two temperature rise speed to 1450°C. Bending strength of AGC that was made by lower temperature rise speed to 1400°C was the lowest. The Vicker’s hardness of the 1450°C groups was higher than that of the 1400°C groups. Conclusion: Both presintering temperature and the temperature rise speed can influenced the properties of AGC, but the effect of presintering temperature was the most.


Sign in / Sign up

Export Citation Format

Share Document