The objective of this publication is to present a quality control methodology for additive manufacturing products made of polymer materials, where the methodology varies depending on the intended use. The models presented in this paper are divided into those that are manufactured for the purpose of visual presentation and those that directly serve the needs of the manufacturing process. The authors also a propose a comprehensive control system for the additive manufacturing process to meet the needs of Industry 4.0. Depending on the intended use of the models, the quality control process is divided into three stages: data control, manufacturing control, and post-processing control. Research models were made from the following materials: RGD 720 photopolymer resin (PolyJet method), ABS M30 thermoplastic (FDM method), E-Partial photopolymer resin (DLP method), PLA thermoplastic (FFF method), and ABS thermoplastic (MEM method). The applied measuring tools had an accuracy of at least an order of magnitude higher than that of the manufacturing technologies used. The results show that the PolyJet method is the most accurate, and the MEM method is the least accurate. The findings also confirm that the selection of materials, 3D printing methods, and measurement methods should always account not only for the specificity and purpose of the model but also for economic aspects, as not all products require high accuracy and durability.

Additive processes allow for almost any manufacturing of screw-threaded joint elements. However, this requires knowledge of the geometrical relationships of a threaded itself and the strength of materials from which the screw-threaded joint is made. Thanks to the development of research...

The article presents the results of strength tests of screw-nut threaded connections made of polymeric materials such as: ABS, PLA, PET-G and RGD720. In order to make physical models, three 3D printing techniques were used: Fused Deposition Modeling (FDM), Fused Filament Fabrication (FFF), and PolyJet. The tests took into account the stresses caused by the axial force generated when the bolt is screwed into the nut or other structural element. Due to the complexity of the issue, the presented studies are only a starting point for further research.

The article presents the results of strength tests in the form of a static tensile test on the INSTRON 5967 testing machine. Samples were made with the use of the Prusa i3 MK3 3D printer, by modeling with a plasticized material (FFF) made of ABS copolymer, polylactide and its modified variant. According to the information provided by the manufacturer, heat-treated modified polylactide has mechanical properties similar to ABS copolymer filament. The publication also discusses the method of manufacturing elements subjected to the tests, the heat treatment process, as well as changes in material properties as a result of this treatment. Based on the test results, it was found that the annealing process increased the proportion of the crystalline phase, which significantly improved the strength properties of the modified polylactide.

The application of direct metal laser sintering renders it possible to manufacture models with complex geometries. However, there are certain limits to the application of this method connected with manufacturing thin-walled cuboidal elements, as well as cylinders and holes with small diameters. The principal objective of the research was to determine the accuracy of manufacturing geometries with small cross-sections and the possibility of application in heat exchangers that are radiators with radially arranged ribs. To that end, four specimens were designed and manufactured; their geometries of representations assumed for the purpose of research (analysis) changed dimensions within the following scope: 10–0.1 mm. The specimens to be applied in the research were manufactured with 17-4 PH stainless steel (1.4542) with the application of 3D-DMLS printing and an EOS M270 printer. The measurement of accuracy was performed with the application of an optical stereomicroscope (KERN OZL-466). In addition to that, research into the chemical composition of the material, as well as the size of spherical agglomerates, was conducted with the application of a scanning electron microscope. The analysis of the chemical composition was conducted as well (after the sintering process). The analysis of the results based on the values received by means of measurements of the manufactured geometries was divided into three parts. Based on this, it is possible to conclude that the representation of models manufactured with the application of DMLS was comparable with the assumptions, and that the deviations between a nominal dimension and that received in the course of the research were within the following scope: 0–0.1 mm. At the final stage of research and based on the received results, two heat exchangers were manufactured.

The purpose of the undertaken research work is to analyze the torsional strength of standard samples with a circular cross-section, produced additively using the SLS (Selective Laser Sintering) technique – sintering PA2200 polyamide powders. The studies conducted so far have not included a...