The presented article focuses on measurements of extremely small dimensions in nanometrology using tactile probes. It addresses a newly developed method of precise measurements in nanometrology by touch probes, where the measurements are carried out on the machine SIOS NMM-1. The aim of this work is to determine accuracy of measurements on this machine. The main contribution of this work is a creation of a methodology for the measurement of precision parts and determination of accuracy of measurement when using this device in nanometrology. The work also includes methodology for the calculation of measurement uncertainty, a keystone in determining the accuracy of measurement in nanometrology. The article provides results of representative sets of measurements of ruby ball diameters, including the evaluation of statistical parameters and determination of the combined measurement uncertainty.

The influence of high doses of beta radiation on the changes in the structure and selected properties (mechanical and thermal) polymers were proved. Using high doses of beta radiation for polybutylene terephthalate (PBT) and its influence on the changes of mechanical properties of ultra nanohardness has not been studied in detail so far. The specimens of polybutylene terephthalate (PBT) were made by injection moulding technology and irradiated by high doses of beta radiation (0, 33, 66 and 99 kGy). The changes in the microstructure and micromechanical properties of surface layer were evaluated using FTIR, WAXS and instrumented ultra nanohardness test. The results of the measurements showed considerable increase in mechanical properties (indentation hardness, indentation elastic modulus) when the high doses of beta radiation are used.

Regarding the very dynamic development of the non-contact measurement methods, there has been observed still increasing number of their applications in various fields during the last years -not only in the engineering industry. E.g. from the dimensional quality point of view, knowledge of real 3D data of a given part is truly very important. There are several options for obtaining these data such as the usage of optical 3D digitization or computed tomography (CT). However, within the mutual comparability of such data, it is very important to know not only the accuracy of acquiring 3D data, but also e.g. possibilities of these systems in terms of own measurement. In the paper, a specially designed part containing various convex and concave shapes was measured by using two different systems (ATOS TripleScan optical 3D scanner and METROTOM 1500 G2 CT scanner). The resulting scanned models were then compared not only in terms of dimensional accuracy, but also in terms of quality and detail of the obtained data or the time required to prepare the measurement and its implementation.

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The work deals with the influence of process parameters on the quality and accuracy of parts produced by FDM (Fused Deposition Modelling)/FFF (Fused filament fabrication) technologies. The experiments were carried out on the 3D Ultimaker printer, PLA (Polylactid Acid) thermoplastics were used as the test materials. The practical part is divided into 3 experiments. First, the optimum temperature was set. In the next part, the parameters of retraction rate, retraction length and crossing speed were determined. In the last part, the impact of 13 parameters on the printing time, material consumption, surface quality and accuracy were determined. In this part of the experiment, the effect of the factors on the quality indicators was determined using the DoE Taguchi methodology. Subsequently, the influential parameters were determined by Paret's rule. The results showed how layer height and print speed are the most important factor for the print time. The parameters-percent filling, number of walls, and the height of the layer were marked as essential parameters affecting the material's consumption. The surface roughness and dimensional accuracy are most influenced by the height of the layer.

This contribution assesses the possibilities of application of volumetric compensation technology on a small three-axis vertical machining centre. These machine tools are designed for machining of small workpieces with various requirements on dimensional and shape accuracy. Small machine tools do not show large volumetric deviations across the entire working space as it is seen with medium-sized and large machining centres. To test volumetric compensation, detailed measurements on a small machining centre (demonstrator) were performed prior to activation of compensation set; other verification measurements were carried out with activated compensation set. Even if volumetric compensation is deployed, it is necessary to verify the achieved results in an appropriate manner. The accomplished study will offer pertinent conclusions on the appropriateness of the technology to be deployed for selected types of workpieces.

Using optical 3D digitisation for dimensional and shape inspection of work-pieces became a trend recently. Before a 3D scanning process starts, surface of the measured part must usually be coated with a thin layer of anti-reflective material. Such surface coating can be performed by means of a wide range of products with various composition and application method. It is however important to know how the matt coating affects the quality and accuracy of digitization, what the structure and thickness of a coating are. The thickness of a coating may vary significantly from product to product and according to our research, it ranges between units and hundreds of µm. This article presents results of an extensive research of seven matt coating products commonly used in practice. The measurement was carried out on cylindrical and spherical elements using ATOS optical 3D scanner and an electron microscope. Thereafter, the measurement results were analysed to define how the applied coating product along with the material of measured object affect the work-piece dimensional properties. The ease of coating removal was evaluated in the research as well.

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