The effect of 3D printing parameters by Fused Filament Fabrication (FFF) on the translucency of polylactic acid (PLA) parts was investigated. Six different printing parameters were studied: object orientation, layer height, nozzle temperature, fan speed, extrusion multiplier, and printing speed. The commercially available Plasty Mladeč PLA filament and the Original Prusa MK4 3D printer were used for the experiments. The translucency of the printed samples of 50 × 25 × 1 mm dimensions was measured using a luxmeter in an integrating sphere. A total of 32 sample combinations were created. Each sample was printed ten times. The results show that all investigated parameters significantly affect the optical properties of PLA parts. The best measured translucency values were obtained when printing in portrait mode, with a layer height of 0.30 mm, nozzle temperature of 240 °C, fan speed of 100%, 0.75 set extrusion multiplier, and a speed of 40 mm/s. ANOVA was used to statistically evaluate the effect of each parameter on translucency, and statistically significant differences were found between different combinations of parameters (p < 0.05). Scanning Electron Microscope (SEM) analysis provided detailed images of the surface structure of the printed samples, allowing for a better discussion of the microscopic properties affecting the translucency. The best print setting has an efficiency of 88% compared to the default setting of 65%. The ability of visible light to pass through the print (translucency) improved by 23%.

Machining is an important part of the manufacturing process in the engineering field. Turning is one of these areas. At present, almost exclusively exchangeable cutting inserts are used in production machining. The article describes the research in the field of their wear, where the electron microscopy was used to evaluate the results. Electron microscopy is a very important aid in research in many areas not only of human activity and also is the important aid in the field of mechanical engineering and manufacturing technologies. The results thus obtained can make in a given area it clearer and better document the resulting situation. Within the experiments, selected cutting inserts (WPP10S, WPP20S) were used and the given material was machined (34CrNiMo6 steel). The cutting speed was different depending on the type of insert (WPP10S 120 and 140 m•min-1 , WPP20S 80, 100 and 120 m•min-1). The electron microscope Tescan Vega 3, which is available in the workplace where the experiment was conducted, was used to evaluate the resulting tool wear. As part of experiments was also realized the composition analyze of used cutting inserts. Analyzes of the machined material were also performed to confirm the declarations from the supplier.

This article deals with the comparative wear of CNMG-coated sintered carbide indexable cutting inserts by several manufacturers when turning 1.6582 steel hardened to 40–44 HRC. The main goal will be to demonstrate the different course of wear by testing seemingly identical inserts for engineering companies, showing the connection between the course of wear and the production of waste in the form of chips. The monitored type of wear was the flank wear VB_max of a cutting tool depending on the length of the machining time. Additionally, the effect of cutting tool wear on chip production, i.e., their quantity, shape and size, was monitored. For the purpose of mutual comparison, uniform cutting conditions were chosen on the basis of previous experiments, ensuring the stability of the given cutting process. For flank wear analysis, optical and electron microscopes were used. Meanwhile, a portable roughness tester was used to analyze the roughness of the machined surface. It was found that the quality of the interconnected coating layers has a perceptible influence on wear rate of the evaluated cutting inserts. The relation between the degree and characteristics of wear on the one hand, and the properties of the produced chips that identify the effect of the difference in the deposition layers using EDX/SEM analysis on the other, foreshadows the importance of choose between products with similarly declared properties was found. The current assessment of cutting tool wear and the evaluation of the chip produced has significant economic potential for manufacturing companies seeking to minimize costs.

This article deals with a mutual comparison of indexable cutting inserts of the CNMG 120408 type from two different manufacturers during the machining of hardened steel AISI 4337 and austenitic stainless steel AISI 316 L. The main goal is to analyse the different wear processes depending on the difference in the manufacturer’s design and also depending on the properties of the different machined materials. The progress of the wear of the main spine of the tool, the types of wear and the service life of the cutting edge were monitored, with the achievement of the critical value VB_max = 300 µm being the standard. In addition to the wear of the inserts, the production of chips was monitored in terms of their shape, average size and number of chips per 100 g of chips produced. In order to understand the relationships arising from the obtained data, an SEM equipped with an elemental analyser was used to analyse the coating layers and the substrate of the unworn inserts and the types of wear and the intensity of the surface damage of the worn inserts. A several-fold difference in the lifetime of the cutting edge was found, both in terms of design and in terms of the selected machined material, while in both cases the cutting edge with Al₂O₃ and TiCN layers of half thickness achieved a better result in liveness. From the point of view of chip formation, very similar results in shape and average length were observed despite the different designs of chip breakers. Cutting inserts with half the thickness of the coating layers achieved longer cutting edge life in the non-primary material application compared to the target workpiece material. At the same time, it was observed that a thinner coating layer has a positive effect on chip formation in terms of its length and shape.

This article is about comparison of the wear of indexable CNMG carbide inserts from two different manufacturers when turning austenitic stainless steel 1.4404, which is not intended as the primary material to be machined from the point of view of the tested inserts. The main goal was to detect the different course of wear after testing inserts of the same type according to ISO 6987 showing the connection between the design and processing of the inserts in connection with the selected cutting parameters. The type of wear that was observed was the main flank wear VBmax, depending on the length of the machining time. Optical and electron microscopes were used to analyze the flank wear. According to the assumption, it was found that the layout of the cutting edge geometry and coating layers has a noticeable effect on the degree of wear of the evaluated cutting inserts. At the same time, it was found that the tested indexable inserts achieved very good service life values despite the fact that the tested material does not belong to the primary use group. Evaluation of cutting tool wear has a major economic potential for manufacturing companies attempting to minimize costs by trying to use as many universal cutting tools as possible or looking for opportunities to expand the applications of already used cutting tools.