scholarly journals Impact of Thermal Treatment on Anatomical and Mechanical Properties of Ricinodendron heudelotii Wood

Author(s):  
E. A. Iyiola ◽  
S. O. Ayanleye ◽  
O. Catherine ◽  
B. Olufemi ◽  
F. A. Faruwa ◽  
...  

The study examined the impact of thermal treatment on anatomical and mechanical properties Ricinodendron heudelotii wood. Wood samples were oven dried at 105°C and cooled in a desiccator to a constant weight before the thermal treatment. Heat treatment of wood was carried out in a Furnace at 120°C, 140°C and 160°C for 45 minutes and 90 minutes. The Density, Modulus of Elasticity (MOE), Modulus of Rupture (MOR), and the anatomical properties were assessed. The results for Density of Ricinodendron heudelotii wood showed decrease from 279 kg/m3 (120°C at 45 minutes) to 256 kg/m3 (160°C at 90 minutes) while that of control was 281 kg/m3   which was lower than the treated samples. The increase in temperature with time had effect of the color of wood as it changed from creamy white to dark brown. The image of untreated and treated samples showed no significant changes within and among treatment groups as there was no effect of treatment time and exposure on the samples. The MOE of heat treated Ricinodendron heudelotii increased from 2064.84 N/mm2 (140°C for 45 minutes) to 2271.93 N/mm2 (160°C for 90 minutes) while MOR decreased from 40.56 N/mm2 (140°C for 90 minutes) to 33.53 N/mm2 (160°C for 90 minutes). The study revealed that the wood could be used in a light furniture as unnecessarily heavy wood is not important. Also, the study proved effective in improving the modulus of elasticity of the wood.


BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 9596-9610
Author(s):  
Yali Shao ◽  
Lili Li ◽  
Zhangjing Chen ◽  
Sunguo Wang ◽  
Ximing Wang

Poplar (Populus) wood was subjected in this work to thermo-hydro-mechanical treatment. The influence of the treatment parameters on the physical and mechanical properties were investigated. The wood samples were densified under three compression ratios (0%, 30%, and 50%), and thermally treated at three temperatures (180 °C, 200 °C, and 220 °C), at three thermal treatment durations (3 h, 4 h, and 5 h). The density, modulus of elasticity, modulus of rupture, radial hardness, and thickness swelling were measured. The results showed that the densities of the samples increased by 36.6% to 49.7%. As the compression rate increased, the temperature, duration, modulus of elasticity, modulus of rupture, and hardness increased. However, the dimensions of the densified samples were less stable. Compared to the densified samples, the maximum thickness swelling could be reduced by 74% (from 29.7% to 7.8%) when subjected to a thermal treatment at 220 °C for 3 h.



BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 7006-7020
Author(s):  
Ricardo Acosta ◽  
Jorge A. Montoya ◽  
Carlos A. Londoño

Lignocellulosic materials that are thermally treated via hydrolysis react chemically, modifying their internal structure, which in turn modifies their physical and mechanical properties, as well as their dimensional stability. Bamboo (Guadua angustifolia Kunth) samples 3 years old, without nodes and without skin, obtained from their basal area were subjected to thermal treatment with temperatures between 160 and 200 °C and duration times between 1 h and 4 h. The severity of the thermal treatment affects the modulus of rupture and modulus of elasticity in compression. The modulus of rupture increased at temperatures up to 180 °C with treatment times of 2 h, i.e., the severity, defined as the product of the temperature and the time varied between 320 (°C*h) and 360 (°C*h). An inflection point was obtained at a temperature of 180 °C after 2 h with a maximum value of 115.1 MPa. The modulus of elasticity increased as the temperature and time increased. The modulus of rupture and the modulus of elasticity of the treated samples increased up to 14.7% and 36.1%, respectively, compared to the not thermal treated samples. Additionally, when the density increased, the resistance and the compression stiffness also increased.



2016 ◽  
Vol 8 (15) ◽  
pp. 47-54
Author(s):  
Haspiadi Haspiadi

The purpose of this research is to know the influence of pressure and use of conplast against mechanical properties which are a Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) of plasterboard. The study is done because still low quality of plasterboard made from a mixture of ashes of oil-palm shell especially of the mechanical properties compared to the controls. The method of this reserach used variation of printed pressure and the addition of conplast. Test result is obtained that the highest value of Modulus of Elasticity (MOE) 90875.94 Kg/cm2, Modulus of Rupture (MOR) 61.16 Kg/cm2 and density values in generally good printed at the pressure 60 g/cm3 and the addition of conplast 25% as well as the composition of the ash of palm shell oil 40%: limestone 40%: cement 15%: fiber 5% and 300 mL of water. ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui pengaruh tekanan dan penggunaan conplast terhadap sifat mekanik yaitu kuat lentur dan keteguhan patah eternit berbahan dasar abu cangkang sawit. Penelitian ini dilakukan karena masi rendahnya mutu eternit berbahan campuran abu cangkang sawit dari bolier khususnya sifat mekanik dibandingkan dengan kontrol. Metode penelitian yang digunakan adalah dengan variasi tekanan cetak dan penambahan conplast. Hasil uji diperoleh bahwa kuat lentur tertinggi sebesar 90875,94 Kg/cm2 dan keteguhan patah sebesar 61,16 Kg/cm2, yang dicetak pada tekanan 60 g/cm3 dan penambahan conplast 25% dengan komposisi  abu cangkang sawit 40 %: kapur 40 % : semen 15 %: serat 5 % dan air 300 mL.Kata Kunci :  Abu cangkang sawit, conplast, kuat lentur, keteguhan patah.



2016 ◽  
Vol 35 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Zhiyuan Liang ◽  
Wanhua Sha ◽  
Qinxin Zhao ◽  
Chongbin Wang ◽  
Jianyong Wang ◽  
...  

AbstractThe effect of aging heat treatment on the microstructure and mechanical properties of 10Cr20Ni25Mo1.5NbN austenitic steel was investigated in this article. The microstructure was characterized by scanning electron microscopy, energy dispersive spectrometry and transmission electron microscopy. Results show that the microstructure of 10Cr20Ni25Mo1.5NbN austenitic is composed of austenite. This steel was strengthened by precipitates of secondary phases that were mainly M23C6 carbides and NbCrN nitrides. As aging treatment time increased, the tensile strength first rose (0–3,000 h) and then fell (3,000–5,000 h) due to the decrease of high density of dislocations. The impact absorbed energy decreased sharply, causing the sulfides to precipitate at the grain boundary. Therefore, the content of sulfur should be strictly controlled in the steelmaking process.



2014 ◽  
Vol 1025-1026 ◽  
pp. 42-45 ◽  
Author(s):  
Luiz A. Melgaço N. Branco ◽  
Eduardo Chahud ◽  
André Luis Christoforo ◽  
Francisco Antonio Rocco Lahr ◽  
Rosane A.G. Battistelle ◽  
...  

This study aimed, with the aid of analysis of variance (ANOVA), to investigate and quantify the influence of moisture ranging between 12% and over 30% (fiber saturation) on the mechanical properties: strength and modulus of elasticity in compression and in tension parallel to grain; modulus of rupture and modulus of elasticity in static bending; shear strength parallel to grain considering wood species Ipê (Tabebuia sp) and Angelim Araroba (Vataireopsis araroba). Tests were performed according to the assumptions and calculating methods Brazilian standard ABNT NBR 7190, Anexx B, totalizing 400 tests. Results of ANOVA revealed a significant reduction (16% on average) for mechanical properties wood due to the increase in moisture content from 12% to over 30% (fiber saturation). The same behavior also occurred when assembly containing the two species was considered.



2007 ◽  
Vol 344 ◽  
pp. 383-390 ◽  
Author(s):  
Marion Merklein ◽  
Uwe Vogt

Tailored Heat Treated Blanks (THTB) are blanks that exhibit locally different strength specifically optimized for the succeeding forming process. The strength distribution is set by a local, short-term heat treatment modifying the mechanical properties of the material. Hence, THTB allow enhancing forming limits significantly leading to shorter and more robust manufacture process chains. In order to qualify the use of THTB under quasi series conditions, the interdependencies of the blank’s local heat treatment and the entire process chain of the car body manufacture have to be analyzed. In this respect, the impact of a short-term heat treatment on the mechanical properties of AA6181PX, a commonly used aluminum alloy in today’s car bodies, was studied. Also the influence of a short-term heat treatment on the coil lubricant, usually already applied by the material supplier, was given a closer look. Based on these experiments process restrictions for the application of THTB in an industrial automotive environment were derived and a process window for the THTB design was set up. In conclusion, strategies were defined how to enhance the found process boundaries leading to a more robust process window.



Author(s):  
Tiago Cavalcanti IWANAGA ◽  
José Lamartine de Andrade AGUIAR ◽  
Euclides Dias MARTINS-FILHO ◽  
Flávio KREIMER ◽  
Fernando Luiz SILVA-FILHO ◽  
...  

ABSTRACT Background: The use of measures in colonic anastomoses to prevent dehiscences is of great medical interest. Sugarcane molasses, which has adequate tolerability and compatibility in vivo, has not yet been tested for this purpose. Aim: To analyze the biomechanical parameters of colonic suture in rats undergoing colectomy, using sugarcane molasses polysaccharide as tape or gel. Methods: 45 Wistar rats (Rattus norvegicus albinus) were randomized into three groups of 15 animals: irrigation of enteric sutures with 0.9% saline solution; application of sugarcane molasses polysaccharide as tape; and sugarcane molasses polysaccharide as gel. The rats underwent colon ressection, with subsequent reanastomosis using polypropylene suture; they were treated according to their respective groups. Five rats from each group were evaluated at different times after the procedure: 30, 90 and 180 days postoperatively. The following variables were evaluated: maximum rupture force, modulus of elasticity and specific deformation of maximum force. Results: The biomechanical variables among the scheduled times and treatment groups were statistically calculated. The characteristics of maximum rupture force and modulus of elasticity of the specimens remained identical, regardless of treatment with saline, polysaccharide gel or tape, and treatment time. However, it was found that the specific deformation of maximum force of the intestinal wall was higher after 180 days in the group treated with sugarcane polysaccharide gel (p=0.09). Conclusion: Compared to control, it was detected greater elasticity of the intestinal wall in mice treated with sugarcane polysaccharide gel, without changing other biomechanical characteristics, regardless of type or time of treatment.



2020 ◽  
Vol 36 (2) ◽  
Author(s):  
Marta Cristina de Jesus Albuquerque Nogueira ◽  
Victor Almeida de Araujo ◽  
Juliano Souza Vasconcelos ◽  
André Luis Christoforo ◽  
Francisco Antonio Rocco Lahr

Forest Red Gum eucalypt provides a versatile wood and is converted into different purposes. However, such wood is somewhat limited in structural ends, which highlights the need to exploit this gap through diffusion of mechanical properties of such timber. Obtained results should assist engineers and architects in decision-making for its best building application. This paper studied two physical and fourteen mechanical properties evaluation of Eucalyptus tereticornis at two different moisture contents, following the prescriptions of Brazilian (ABNT NBR 7190: 1997) and North American (ASTM D-143-14: 2014) standard documents. Thus, 1091 repeats were carried out for all properties. By a moisture reduction from 30% to 12%, the bulk density and eleven strength properties statistically showed changes such as modulus of rupture (static bending, parallel and perpendicular compressions), modulus of elasticity (perpendicular compression and static bending), shear stress, tangential cleavage, and parallel and perpendicular hardnesses. Then, the Eucalyptus tereticornis timber could be better usable if is further applied for structural construction uses.



2021 ◽  
Vol 3 (1) ◽  
pp. 41-44
Author(s):  
Nur Wafa Amalina Amali ◽  
Nor Yuziah Mohd Yunus ◽  
Wan Mohd Nazri Wan Abdul Rahman

In this study, mechanical properties of commercially manufactured hybrid particleboard from mix-tropical wood and rubberwood with four different densities at 25mm thickness have been investigated. The particleboard sample cutting and testing was in accordance to EN312:2013. The density of particleboard is identified with interval of 10kg/m3 for different densities which include 660kg/m3, 670kg/m3, 680kg/m3 and 690kg/m3. Particleboards were made with the ratio of 40:60 for mix-tropical wood particle and rubberwood particle respectively. The particleboards were prepared with urea formaldehyde (UF) with E1 formulation with addition of wax and hardener.  Increment of 10kg/m3 density for each particleboard led to increase in internal bonding (IB), bending testing include modulus of rupture (MOR) and modulus of elasticity (MOE), surface soundness (SS) and screw edge (SE) withdrawal. It was found that with board increment of 10kg/m3, the improvement was not statically significant except that for MOR. All panels met the minimum requirements of standard.



1995 ◽  
Vol 117 (2) ◽  
pp. 479-488 ◽  
Author(s):  
D. D. Hall ◽  
I. Mudawar

The mechanical properties of age-hardenable aluminum alloy extrusions are critically dependent on the rate at which the part is cooled (quenched) after the forming operation. The present study continues the development of an intelligent spray quenching system, which selects the optimal nozzle configuration based on part geometry and composition such that the magnitude and uniformity of hardness (or yield strength) is maximized while residual stresses are minimized. The quenching of a complex-shaped part with multiple, overlapping sprays was successfully modeled using spray heat transfer correlations as boundary conditions within a finite element program. The hardness distribution of the heat-treated part was accurately predicted using the quench factor technique; that is, the metallurgical transformations that occur within the part were linked to the cooling history predicted by the finite element program. This study represents the first successful attempt at systematically predicting the mechanical properties of a quenched metallic part from knowledge of only the spray boundary conditions.



Sign in / Sign up

Export Citation Format

Share Document