Browsing by Subject "additive manufacturing"

Now showing 1 - 10 of 10

Access status: Open Access ,
A universal convolutional neural network for the pixel-level detection and monitoring of weld beads
(Wydawnictwa AGH, 2024) Wang, Zhuo; Kayitmazbatir, Metin; Banu, Mihaela
In weld-based manufacturing processes such as welding and metal deposition additive manufacturing (AM), the weld bead is a direct indicator of manufacturing quality. For example, the geometry of the weld bead was optimized to a net shape which outperformed conventional geometries. Automatic monitoring of weld bead is thus of prime importance for welding process control and quality assurance. This paper develops a general-purpose convolutional neural network (CNN) for pixel-level detection and monitoring of beads, regardless of welding materials, machine, manufacturing conditions, etc. To achieve the generality, we collected a great variety of welding images containing 2677 single-line beads from 231 research articles, followed by pixel-wise hand-annotation. Consequently, the trained CNN can recognize different beads from various backgrounds at a pixel level. Case studies show that compared to the image-level classification in prior research, its pixel-level labeling permits real-time, complete characterization of weld beads (e.g., detailed morphology, discontinuity, spatter, and uniformity) for more informed process control. This research represents a significant step towards developing a truly human-like monitoring system with low-level scene understanding ability and general applicability.
Access status: Restricted ,
Badania wpływu absorbcji wody na właściwości wytrzymałościowe poliamidu PA12 wytwarzanego metodą druku 3D SLS
(Data obrony: 2017-09-28) Piasecki, Bartłomiej
Wydział Inżynierii Mechanicznej i Robotyki
Access status: Restricted ,
Development, optimization and characterization of zirconia and alumina-zirconia UV-curable slurries for Digital Light Processing
(Data obrony: 2019-07-11) Szubra, Natalia
Wydział Inżynierii Materiałowej i Ceramiki
Access status: Open Access ,
Evaluation of 3D-printed Pattern Material for Heat-hardened Inorganic Moulds
(Wydawnictwa AGH, 2024) Jalava, Kalle; Anwar, Nurul; Orkas, Juhani
Inorganic binders for sand moulding are currently of high interest due to the need to lessen our environmental impact and emissions. In this study, a heat hardened solid inorganic sodium silicate binder was tested with a 3D printed resin material to see how the use of such a material affected a silica mould’s quality, e.g. surface roughness. Results were compared to moulds made with metallic patterns. The unmodified binder had sticking issues when used with a metallic pattern, resulting in a rough as-moulded surface. Such issues were not seen with the printed resin patterns, also hinting at good performance with binders that contain performance increasing additives. The resin pattern material has a Heat Deflection Temperature (HDT) of 230°C, enabling the use of inorganic binders that require temperatures between 160–200°C to harden and dry. Additive manufacturing of such materials also allows designs for other hardening techniques than furnace heating, such as microwave heating. The moulds hardened with microwaves did not exhibit sticking issues. Additive manufacturing of tooling is a potential source of geometrical variation in final castings and are also studied in this work. In general, switching from traditional sand moulding patterns used with organic binder systems to inorganic systems, the patterns and core boxes need to be replaced by new ones made of a metallic or other heat resistant material. The studied material is a promising option for such a switch, especially when a complex shape enabled by additive manufacturing is also required.
Access status: Open Access ,
Identification of the heat source and thermal material model parameters for the laser engineered net shaping
(Wydawnictwa AGH, 2022) Hajder, Lucyna; Zhang, Tao; Nguyen, Vu
The research's primary goal is to identify the heat source and thermal material model parameters for the numerical simulation of the laser engineered net shaping (LENS). Inconel 718 was selected as a case study for the current investigation. The LENS process's numerical model was developed within commercial finite element software and was used as a direct problem model during the parameter identification stage. Experimental data were obtained based on a rectangular-shaped sample with thermocouples located under the based material surface. The recorded thermal profiles were used to establish a goal function for the parameter identification stage. As a result, parameters describing the melt pool geometry during the additive manufacturing, as well as thermal coefficients describing interactions between the sample material and surrounding/base material, were determined.
Access status: Open Access ,
Influence of structural characteristics on the mechanical properties of FDM printed PLA material
(AGH University of Science and Technology Press, 2020) Szczepanik, Stefan; Nikiel, Piotr
The present study reports on the influence of printing process parameters, architecture, raster, infill orientation and filling on the density, macrostructure, and mechanical properties, including impact resistance, of biodegradable polymer parts fabricated in polylactide (PLA) on a desktop printer. It complements and considers phenomenologically the results of recently published similar studies, including the use of recycled filament. In our study, complex mechanical properties for the samples printed at the same time on a Replicator 2 printer were investigated. Three samples were printed for each test. Full mechanical characteristics (tensile, compression and bend strengths and impact resistance) of the printed PLA material are reported. This is the novelty in comparison to other studies, where the samples test were printed individually or in a series for each test. The shape and thickness of the layered macrostructure, the presence of holes inside the layers, the number of shell perimeters and the fill density all influenced the tensile properties of the printed materials. These results show the possibility of printing with a 0.3, i.e. shorter printing time than 0.1, 0.15 and 0.18 mm layer thicknesses also reported, without significant decrease in mechanical properties. It is interesting to note that the compressive strengths, the yield of 70-80 MPa and a UTS 113-120 MPa for the printed material with a fill density of 94-96% are comparable with those of aluminum.
Access status: Open Access ,
Investigation of the suitability of a fused filament fabricated tool for incremental sheet metal forming
(Wydawnictwa AGH, 2023) Weise, Dieter; Langner, Christian; Pierer, Alexander; Kraeusel, Verena; Petru, Jana; Koziorek, Jiri; Prauzek, Michal
Incremental sheet forming (ISF) is a flexible manufacturing process for sheet metal parts in small to medium quantities. Successive movements of a stylus create the geometry of the sheet metal part. ISF can be performed with or without a counter tool. By using counter tools, the geometry deviation of the formed sheet metal part can be reduced. To achieve the broader application of ISF, counter tools must be cost-effective, fast, and individually producible, even for batch sizes of only one part. In addition to milling, which has been the main method used to date, additive manufacturing (AM) also makes it possible to meet these requirements for flexible counter tool production. To investigate the suitability of AM for the production of counter tools for the ISF and to learn more about the load on the counter tool, a cylindrical counter tool made of polylactic acid (PLA) was produced using the fused filament fabrication (FFF) process. This counter tool was used for the ISF of drawing steel. Based on the force measurement results, a first step towards suitability evaluation of 3D-printed counter tools for ISF was taken, and possibilities, as well as application limits for such counter tools were discussed.
Access status: Open Access ,
Possibilities of manufacturing spatial elements using the 135 hardfacing method
(Wydawnictwa AGH, 2023) Góral, Tomasz; Krawczyk, Stanisław; Pawlik, Jan
3D printing with thermoplastic materials is slowly becoming commonplace as additive manufacturing has gained a large number of dedicated users over the past few years, and the prices of the requisite equipment have significantly dropped. However, in terms of materials, only plastics have enjoyed this popularity. Although metals are, in a sense, thermoplastic materials, their spatial application would require very advanced setups, which in turn generates high costs and complicates process control. This article discusses the possibilities of the additive manufacturing of metal elements using a three-axis numerically controlled plotter combined with a semi-automatic welding machine using the 135 method. The authors also examined the impact of sudden changes in velocity vectors on geometric deviations.
Access status: Open Access ,
Projekt, optymalizacja i wykonanie prototypu sportowego zacisku hamulcowego do motocykli z wykorzystaniem technologii przyrostowych
(Wydawnictwa AGH, 2025) Adamiec, Karol
W niniejszym artykule przedstawiono prototyp motocyklowego zacisku hamulcowego, zaprojektowanego z myślą o produkcji przyrostowej technologią SLM ze stopu Ti6Al4V. Celem projektu była maksymalna redukcja masy w stosunku do pierwotnego korpusu zacisku przy jednoczesnym zachowaniu wymaganej wytrzymałości w warunkach eksploatacyjnych. W ramach pracy wykorzystano inżynierię odwrotną z zastosowaniem technologii skanowania 3D światłem strukturalnym, co pozwoliło na zachowanie kompatybilności z wybranym motocyklem. Geometrię prototypowego zacisku opracowano na podstawie analiz symulacji naprężeń oraz optymalizacji MES, uwzględniając wyznaczony układ obciążeń w warunkach maksymalnego hamowania. Artykuł prezentuje postępowanie projektowe, oparte na optymalizacji konstrukcji dla technik produkcji przyrostowych i nadające się do adaptacji w produkcji szerszej grupy podzespołów motoryzacyjnych.
Access status: Open Access ,
The role of die definition in the numerical simulations of two-points incremental forming processes
(Wydawnictwa AGH, 2023) Perzyński, Konrad; Pawlikowski, Kacper; Madej, Łukasz
The main objective of this work is to investigate the influence of the definition of dies type in the finite element simulation of the two-points incremental forming processes (TPIF). Particular attention is on determining the effect of assigning elastic properties for the 3D printed dies or considering fully rigid on the final results. During the research, three different shapes of dies were analyzed. Simulation results in the form of sheet thickness distributions and measured forces are presented for comparison purposes.