This paper presents the particle-size distribution of dust created by the drilling of selected wood composites, which was carried out using a CNC machine. The particle-size distribution was studied through two methods. Two analyses were performed: the sieve analysis of samples from the whole mass of collected dust and the laser diffraction analysis of the finest fraction isolated by sieving. The results presented general information about the particle-size distribution of the dust, as well as detailed information on the content of the finest particles. This information revealed that the particles might pose a potential risk to the health of workers employed in the woodworking industry. This potential risk is due to the possibility of their dispersion in the atmosphere surrounding the workplace and their size, which allows them to be respirable. The relationship between the fineness of the dust and the type of wood composite was also tested. Most ultrafine particles are formed during the drilling of fibreboards and are especially produced in traditional wet technology.

The study aimed to determine the suitability of agricultural lignocellulosic biomass in the form of vine pruning waste for particleboard production. Two variants of particleboards with densities of 650 kg/m³ and 550 kg/m³ containing a varied amount of vine pruning waste (0, 25, 50 and 100%) were evaluated. The strength (MOR, MOE and IB), thickness swelling and water absorption after immersion in water for 2 and 24 h were tested. The results revealed that vine pruning waste affected the board thickening and reduced strength properties. Boards with a 50% share of waste met the minimum requirements of strength properties specified in the EN 312 standard for boards with a density of 650 kg/m³. However, boards with a density of 550 kg/m³ entirely made with vine pruning waste met the minimum requirements of strength properties of the EN 16368 standard. Moreover, the pruned material reduced axial forces during drilling, swelling and water absorption.

The paper presents an automatic approach to recognition of the drill condition in a standard laminated chipboard drilling process. The state of the drill is classified into two classes: “useful” (sharp enough) and “useless” (worn out). The case “useless” indicates symptoms of excessive drill wear, unsatisfactory from the point of view of furniture processing quality. On the other hand the “useful” state identifies tools which are still able to drill holes acceptable due to the required processing quality. The main problem in this task is to choose an appropriate set of diagnostic features (variables), based on which the recognition of drill state (“useful” versus “useless”) can be made. The features have been generated based on 5 registered signals: feed force, cutting torque, noise, vibration and acoustic emission. Different statistical parameters describing these signals and also their Fourier and wavelet representations have been used for defining the features. Sequential feature selection is applied to detect the most class discriminative set of features. The final step of recognition is done by using three types of classifiers, including support vector machine, ensemble of decision trees and random forest. Six standard drills of 12 mm diameter with tungsten carbide tips were used in experiments. The results have confirmed good quality of the proposed diagnostic system.

This paper presents the possibility of using the Spark Plasma Sintering (SPS) method to obtain WCCo composite materials. Such materials are used as cutting blades for machining wood-based materials. Two series of composites, different in grain size and cobalt content, were analyzed in the paper. The produced materials were characterized using Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and tribological properties were determined. In addition, preliminary tests were carried out on the durability of the blades made of sintered WCCo composites while machining three-layer chipboard. The results of the microstructure analysis proved that the SPS method makes it possible to obtain solid composites. Phase analysis showed the occurrence of the following phases: WC, Co, and Co₃W₉C₄. The lowest friction coefficient value was found in samples sintered using powder with an average primary particle size of 400 nm (ultrafine).

This work explores an effect of nitrogen ion implantation on the life time of WC-Co tools used in particleboard milling. Nitrogen ions with different energy of 5, 50, and 500 keV and fluence of 1e17 and 5e17 cm⁻² were implanted into the surface of commercially available WC-Co composite indexable knives, using the implanters with mass-separated ion beams. Both untreated and modified samples were subjected to microstructural and durability tests. Microstructural tests involved surface observation, determination of the nature of wear and cracks, determination of element depth profiles, and phase changes occurring in the modified area. Durability tests were conducted with the use of a computerized numerical control (CNC) machining center. The tests included determination of wear curves and calculation of quantities such as cutting length, relative tool life index, standard deviation, standard error, coefficient of variation and quality index and wear increases. Additionally, a histogram of the relative durability distribution of samples implanted with N⁺ was determined. In this study, an attempt was made to relate the durability results with the microstructure of the knives. Tools modified with a nitrogen ion beam of 50 keV showed the best durability results.

This study investigated the effect of the homogenization of bacterial cellulose particles and their reintegration into a membrane on the mechanical and physical parameters of the films produced from them in relation to films made of native cellulose (not subjected to the homogenization process). Bacterial cellulose was obtained from a culture of microorganisms forming a conglomerate of bacteria and yeast, called SCOBY. The research has shown that the mechanical modification of bacterial cellulose contributes to an increase in the elongation of the material. Modified polymer films were characterized by a higher Young’s modulus and a much higher breaking force value compared to native cellulose. The mechanical modification of cellulose contributed to an increase in hygroscopicity and changes in water vapor permeability. The obtained results may provide significant information on the methods of modifying bacterial cellulose, depending on its various applications.