Advanced Materials Research Vol. 1088

Abstract: The tests used to obtain the stiffness properties of wood are made with two loading cycles, as defined by the Brazilian standard ABNT NBR 7190 (Design of Timber Structures). However, the possibility of reducing the number of cycles allows decrease the operating time of the machine, resulting in reduced spending on electricity used during the tests. This research aimed to investigate, with the aid of the analysis of variance (ANOVA), the influence of the use of three load cycles to obtain the modulus of elasticity in compression parallel to grain (E_c0), in tensile parallel to the grain (E_t0), in bending (E_m) and in compression perpendicular to the grain (E_c90) of Angico Preto (Anadenanthera macrocarpa) wood specie. For the number of cycles and stiffness were manufactured 12 samples, totaling 144 specimens. The results of the ANOVA revealed statistical equivalence between the stiffness properties for both load cycle numbers evaluated, indicating that it is possible to carry out the tests with a single charge cycle, allowing savings in time and energy in the operation of the equipment.

Abstract: This research aimed to develop and evaluation the mechanical properties of a particleboard produced with bamboo particles and coconut fiber in three different experimental conditions. The panels were manufactured with castor oil based polyurethane bi-component resin in three different ratios of the adhesive components (pre-polymer and polyol). Mechanical characterization was conducted to determine modulus of elasticity (MOE) and modulus of rupture (MOR) in static bending. For the static bending test the better values were to the experimental condition 2, which relate de proportion of 1:1.5 of pre-polymer and polyol, respectively. This best solution is to reduce the amount of pre-polymer in the formulation of the adhesive, due to decreased of use of chemicals most polluting.

Abstract: This research aimed to evaluate the influence of storage time (0, 96 hours) of Pinus elliottii pieces and the tests to obtaining modulus of elasticity (static bending and transversal vibration) in glued laminated timber beams, produced with resorcinol based adhesive and 0.8 MPa compaction pressure. After pieces were properly prepared, part of them was used in immediate three manufacturing glulam beams, tested after adhesive cure, and part stored for 96 hours under a roof with a temperature of 25°C and relative humidity of 60% for subsequent manufacturing and testing three other glulam beams. Results of analysis of variance (ANOVA) revealed that the storage period was significant influence in modulus of elasticity obtained in static bending test (8% reduction from 0 to 96 hours). This not occurred with modulus of elasticity obtained by transversal vibration test (no significant influence). ANOVA results showed equivalence of means in both test procedures.

Abstract: Numerous factors influencing the surface quality of wood after machining, among them we highlight the machining parameters and the properties of the wood. In the analysis of the influence of these factors on machining and in determining the quality measurement systems are used to obtain surface characteristics, these systems are divided into methods of contact and non-contact. The method for mechanical contact performed with the aid of the surface roughness tester is the most valued in the measurement of roughness of wood, however, aiming at a greater agility in these measurements, there is a need to seek alternatives for evaluation of surface quality, and one of these options is to use the forms of indirect measurements of this quality, as for example, the use of noise emission during the machining process. With this, the aim was to analyze the influence of the moisture content of the wood, at different levels, on surface quality of the species Pinus elliottii, determined by the method of mechanical probing move and relate this roughness with the sound emission issued for each class of humidity, during machining. The planning of experiments and statistical analyses were performed with the help of Taguchi method. The specimens were conditioned in greenhouses climatizadoras automatics for obtaining three classes of humidity. Machining tests of wooden pieces were performed on a machining center specific for this type of material. The roughness values were measured by a roughness verifier and the noise emission values were measured by for a measurer sound pressure level. Statistically significant differences were observed, the significance level of 10 %, on roughness and noise emission between the three levels of moisture. It was observed that with the increase in the moisture content occurred an increase of roughness and a reduction in noise emission. Monitoring of surface quality through noise level is an interesting alternative to the method of mechanical contact.

Abstract: The objective of the present work was to study the use of bamboo foils as structural reinforcement for MDP wooden panels. Four wooden panels of homogeneous layer were produced using particles of GT1 and RRIM 600 clones of Hevea brasiliensis (rubber tree), and glued with urea-formaldehyde resin (UF). These panels were also overlaid with foils of Phyllostachys edulis (mossô bamboo). The tests were realized to evaluate the physical-mechanical characterization according to European standards (EN). The production of the particleboards with reinforcement of bamboo improves the physical-mechanical characteristics of these commercial wooden panels.

Abstract: The broader knowledge about physical and mechanical properties of wood allows reliable timber structures design. Even little addressed in the literature, in several situations Poisson's ratios are required for the evaluation of stresses acting on structural elements. This study aimed to obtain values of Poisson's ratios (ν), plans Longitudinal-Radial (ν_LR) and Longitudinal-Tangential (ν_LT), for species Peroba Rosa (Aspidosperma polyneuron) and Jatobá (Hymenaea courbaril L.). For this purpose, forty samples Peroba Rosa and eight samples of Jatobá were prepared for testing in compression parallel to the grain, following the recommendations of ABNT NBR 7190 standard. The results of means confidence intervals, considered at the level of 5% significance, revealed that the Poisson's ratios ν_LR e ν_LT to Peroba Rosa are 0.27 and 0.42, respectively, and 0.25 and 0.43 to Jatobá.

Abstract: Leakage was found in certain oilfield offshore pipeline system and investigation results showed that the cause of the leak was corrosion perforation in the sleeve joints of pipeline system. In order to avoid the leak occurring again, it was necessary to analyze corrosion mechanism of the sleeve joints. Macro and micro analyze, test on physical and chemical properties and microstructure, XRD analysis on corrosion products was accomplished on the sleeve joints. Results obtained from analysis and test show that corrosion was stronger because there are some CO2 and H2S in the pipeline together. Corrosion perforation was brought by flow velocity suddenly increase and turbulent flow and flow field action.

Abstract: The application of Ion Plating Plasma Assisted technology in the field of preservation of Cultural Heritage is presented. In order to guaranty the preservation of the artistic and cultural identity of ancient ceramic tiles with strong chromatic valence, not-invasive, and achromatic and antireflective coating deposition processes have been investigated. Different ceramic supports have been utilized for the tests: an ancient tile of the XIX century and contemporaneous production tiles, all characterized by strong chromatic valence and by a mixed porous and glazed surfaces. Ion Plating Plasma Assisted (IPPA) by reactive magnetron sputtering source with Argon and Oxygen atmosphere for TiO₂ and IPPA by thermal source with Argon and Oxygen from SiO material have been adopted. Preliminary tests with two plasma treatments were carried out on contemporaneous tile samples in order to find the optimal processing conditions. TiO₂ treatment has generated miscoloration on the surface of the coating while the SiO₂ coating showed achromatic and transparency properties. The ancient historical tile was used to finally test the optimized process with SiO₂. Traditional organic resin spray coating treatments have been carried out for aesthetical comparative purposes with the new plasma treatment.

Abstract: This experiment consists of two parts. On the one hand is about the concentration of Variation of exhaust gas when heated potteries .On the other hand is about the compared between the potteries (Tang Dynasty) heated by natural gas catalytic combustion furnace and the traditional firing of the glaze. The potteries fired by catalytic combustion furnace could be used for decorating are not only more fine and glossy than the traditional, but also more translucent. Therefore, the potteries made by catalytic combustion furnace will be applied in decoration industries, such as decorative murals.

Abstract: The CrCN coatings was deposited on the substrate of GCr15 steel ball by closed field unbalanced magnetron sputter ion plating. The performances of vibration, temperature rise, rotational speed, load carrying ability and wear resistance of CrCN coatings steel ball bearing and uncoated steel ball bearing were tested by a bearing tester, and also comparatively analyzed. Results show that, compared to the uncoated bearing, the CrCN coatings steel ball bearing, in the case of rotational speeds higher than 5 000 rpm, have lower vibration values, especially above 6 000 rpm, the vibration values were significantly reduced, and the coated bearing has vibration stability performance. And the coated bearing has also slower temperature rise performance, excellent high-speed performance, good load carrying capacity characteristics and wear resistance performance etc.