One main problem in moulding is the proper characterization of the local density of the mould, the best without its destroying, for assessment the quality of the mould and to compare results of compaction modeling with experimental results. Industrial computer tomography (ICT) is a technique that allows the non-destructive and contact-free visualization and characterization of the internal and external parts of physical objects including also sand moulds. It is possible to apply ICT technique for the specific research presented here. Moulding sand compaction plays an important role for the quality of the mould and as the consequence for the quality of manufactured casting. The required quality of the castings can be achieved by selecting optimum manufacturing process parameters. The determination of these parameters is often carried out by trial-and-error-method, which is expensive and time consuming. To improve the understanding of the influence of various parameters, mathematical modeling of the compaction processes using numerical solutions was performed. Theoretical results of the compaction simulations have then been compared with practical results of mould compaction obtained by ICT. It was found that simulation results agree well with data from computer tomography and provide insight into the spatial distribution of the density of sand moulds under industrial condition.Keywords: Industrial computer tomography, sand castings, computer simulation of compaction Podstawowym problemem w procesie formowania jest prawidłowe określenie rozkładu gęstości w formie, najlepiej metodami nieniszczącymi, w celu oceny jakości formy oraz w celu porównania wyników modelowania procesu zagęszczania z wynikami eksperymentu. Przemysłowa tomografia komputerowa -ICT jest techniką, która umożliwia nieniszczącą oraz bezkontaktową wizualizację oraz charakterystykę wewnętrznych oraz zewnętrznych części obiektów fizycznych, w tym również form odlewniczych. ICT jest możliwe do zastosowania w specyficznych badaniach opisanych poniżej. Zagęszczanie masy formierskiej istotnie wpływa na jakość formy i w konsekwencji na jakość wytwarzanych odlewów. Wymagana jakość odlewów może być osiągnięta przez wybór optymalnych parametrów procesu wytwarzania. Określenie tych parametrów często jest dokonywane metodą prób i błędów, co jest kosztowne i czasochłonne. W celu lepszego zrozumienia wpływu różnorodnych parametrów zastosowano matematyczne modelowanie procesu zagęszczania. Wyniki symulacji porównano z wynikami badań zagęszczenia form z zastosowaniem metody ICT. Wykazano zgodność wyników modelowania oraz wyników pomiarów (ICT), co umożliwia określenie przestrzennego rozkładu gęstości w formie piaskowej w warunkach przemysłowych.

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The technology of additive manufacturing (AM) has transformed the fields of machinery, aerospace, and electronics. Adopting cost-effective, precise, and rapid procedures in AM is one of the major concerns of today’s industry. Stereolithography is a promising AM technique that is thought to meet these requirements. However, the fact that materials printed with stereolithography do not have good mechanical properties limits their application, such as in biomedicine and aerospace. Previous studies have shown the shortcomings of stereolithography printers. This research focuses on enhancing the mechanical characteristics of the polymer resin used in stereolithography (SLA)-like liquid crystal display (LCD) 3D printers by fabricating a new AM composite material with carbon fibers. For this reason, chopped carbon fibers (0.1 mm size) at amounts of 0.25 wt% and 0.5 wt% have been used with Acrylonitrile butadiene styrene (ABS)-like photopolymer transparent resin during the printing process, and three different print layer thicknesses were tested. For the design of the experiment (DoE), Q-DAS software was used to analyze the resulting data. A tensile-testing machine was utilized to determine the ultimate strength using the ASTM D638 standard. The results show an increase in the ultimate strength by adding carbon fiber to some extent, but after a certain percentage of carbon fiber added, the strength drops off.

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