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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. [ABSTRACT FROM AUTHOR]

The paper presents the effect of nitrogen ion implantation on the tool life of the tools commonly used in the furniture industry for drilling particleboards. Nitrogen ions with different accelerating voltages of 25, 40, 55, and 70 kV and a fluence of 5 × 1017 cm−2 were implanted into the surface of commercially available high-speed steel (HSS) drills, using the implanters without mass-separated ion beams. The tests were carried out in a computerized numerical control (CNC) machining center used in the furniture industry. Based on the measurements of the direct tool wear indicator (W), the drill wear curves were determined and the relative tool life index, standard deviation, coefficient of variation, and the implantation quality index of tool life were calculated. The studies have shown that the modification of the drill surface layer by the nitrogen ion implantation process increases the tool life. The obtained results allow the research to be the continued in a wider scope. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]