This study evaluated the physical and mechanical characteristics of particleboards made of bamboo waste from the species Dendrocalamus giganteus bonded with two different types of adhesives: urea-formaldehyde (UF) and a castor oil based adhesive (M). Thus, eight types of particleboards were produced in the proportions of 6%, 8%, 10% and 12% for each adhesive. The results showed that particleboards produced with UF and M adhesives had acceptable behavior for physical tests according to the Brazilian standard NBR 14810. The results attained in mechanical tests (MOR and MOE), for all particleboards, were below the requirements for structural usage. This indicates that the residue of bamboo is a feasible raw material alternative for particleboards produced for non structural purposes, such as liners, partitions and other uses for internal seal. Regarding the adhesives, the particleboards produced with UF particleboards showed superior results for both physical and mechanical characteristics, when compared to M particleboards with the same percentage of adhesive.

Medium density fiberboard (MDF) is an industrial product created from lignocellulosic fibers and resin through the combined action of pressure and heat. Have homogeneity, dimensional stability and mechanical strength similar to solid wood. Milling is a machining method widely used within furniture industries; and despite the noteworthy relevance of the subject, there are few specific works dealing with the MDF milling process using computerized numerical control machines. It is increasingly necessary a programmed machining able to generate suitable surface to coatings, allowing for minimum waste and maximum efficiency, besides the decrease of the tool wear. The irregular surface after machining reduces the quality of the final product; this characteristic is defined by measuring the roughness of MDF panel workpieces. Thus, it is possible to quantify the surface quality and improve the machining process with cutting speed, feed rate, depth cut among others. It was observed that roughness exhibited lower values in higher cutting speeds and low feed rates. The 1 mm depth of cut showed optimized surface results. It was concluded that the parameters studied here significantly influence the finishing, resulting in irregular surfaces that can reduce the quality of products.

The sanding process is important to the quality of wood products. Sanding reduces imperfections in wood surfaces and it is important to the final product and application of paints or varnishes. There are few studies about sanding in the literature and finding out the relationship between the input parameters (i.e., species of wood, grit size, abrasive) on the output parameters (i.e., roughness, force, pressure) will help to improve this process. This study analyzed the influence of input parameters as belt speed (cutting speed), grit size and pressure on the output parameters as surface roughness, cutting force (sanding force) and power consumption on cross-grain sanding of Eucalyptus grandis wood. The tests were performed with 3 types of grit sizes (80, 100 and 120 grit), 3 belt speeds (10, 11 and 12 m/s) and 2 pressures (219.89 and 283.44 g/cm²). The surface roughness was analyzed based on roughness average (Ra). Sanding efforts were analyzed by cutting force and power consumption. It was found that the 100 grit size provided the lowest cutting force. It was observed that the belt speed, pressure and grit size influenced the surface roughness, cutting force and power consumption. The best surface finishes were obtained in tests with higher pressure.

The use of fiber metal laminates (FML) in aeronautics components has been increased in the last years, mainly due to the gain in mechanical properties combined with low specific mass. However, in the assembly of these materials on the structures to which they will be attached, mechanical screwing is still the main method used, which requires the performance of drilling processes. Something it is very complicated for these materials and can cause damage that compromises the performance. Therefore, this work aims to approach and summarize the evolution of the mechanical drilling process on FML developed in the last years. By the work, the main problems that occur during the drilling of these materials are punctually approached, such as delamination, burr formation, dimensional error, poor roughness, and tool wear. In addition, it is presented how these problems are affected by the machining parameters (cutting parameters, geometry, material/coating tool, and cutting environment), as well as suggestions for minimizing process problems. Thus, the article intends to provide as much information as possible available in the literature, seeking to help researchers gain a comprehensive view of the mechanical drilling of fiber metal laminates.

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The is paper presents an analysis of the influence of minimum quantity lubrication (MQL), optimized and conventional cooling, using different cutting fluid volumes and flow rates, on the surface quality and integrity of hardened steel workpieces, in cylindrical plunge grinding with superabrasive CBN grinding wheels. The final quality of the workpieces were evaluated based on an assessment of output variables such as the behavior of: tangential cutting force, specific energy, surface roughness, roundness errors, acoustic emission, residual stresses, scanning electron microscopy (SEM) micrographs, and microhardness. The present analysis of the various forms of cutting fluid application identified cooling conditions which favor the minimization of cutting fluid usage, and shorter machining times without impairing the geometrical and dimensional parameters, surface finish and surface integrity of the workpieces. Among the various forms of cutting fluid application, optimized lubrication at higher outlet speeds showed the best performance, confirming the efficiency of the new nozzle concept employed in this study. The optimized and MQL processes were successful in maintaining the hardness and surface integrity of the ground workpieces. The only exception was the use of MQL with a flow rate of 40ml/h, which caused cracking and quenching of the workpiece surface. The lowest surface roughness values obtained with MQL were obtained using higher flow rates of lubricant. The surface roughness values obtained with MQL are high for the grinding process. Low-concentration CBN wheels, which are less expensive and subject to less wear, produce good results when associated with more efficient cutting fluid application techniques.