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The aim of this study is to assess the feasibility of using foundry by-products in porcelain tiles. This feasibility has been evaluated by three different perspectives: technical, radiological and environmental. Firstly, given that the main impurities in foundry by-products are carbon and organic compounds, thermal treatments that successfully reduce carbon and organic compounds have been evaluated. Subsequently, both calcined and uncalcined by-products have been characterised from a technological and radiological point of view and finally, porcelain tile compositions with both calcined and uncalcined by-products have been obtained. These compositions were fully characterised and their performance in the manufacturing process has been evaluated. The environmental impacts of this recycling process were also assessed by means of a life cycle assessment. The results confirm that foundry by-products can partially replace sand in porcelain tile bodies. [ABSTRACT FROM AUTHOR]

Exposure to metal dust is a significant occupational hazard for foundry workers. This study aimed to investigate exposure to potentially toxic metals and oxidative stress indices and assess the health risk of occupational exposure to metal dust among foundry workers. Environmental and biological exposures to a cocktail of metals were examined by measuring the concentration of Aluminum (Al), Zinc (Zn), Copper (Cu), Cadmium (Cd), Nickel (Ni), and Chromium (Cr) in the air of the workplace, as well as in the blood of the exposed workers. Malondialdehyde (MDA), reduced blood glutathione (GSH) and urinary 8- hydroxydeoxy guanosine (8-OH-dG) were measured as biomarkers of oxidative stress. All air measurements were below the maximum allowable limits (MAL) except for Al and Ni according to American Conference of Industrial Hygienists (ACGIH) and National Institute of Occupational Safety and Health (NIOSH). Here is significantly elevated Blood Al, Zn, Cu, and Pb levels in exposed workers. Moreover, MDA and 8-OHdG levels significantly increased (P<0.0001). In contrast, the mean level of GSH was reduced considerably in exposed workers compared to the control group (P<0.0001). The MDA acts as a marker with the highest Area Under the Curve (AUC), enabling effective differentiation between the exposed and control subjects (AUC = 0.968; Sensitivity = 90%, Specificity =100%; P <0.0001). Workers occupationally exposed to these metals for prolonged periods possessed higher metal levels in their bodies, which is associated with increased oxidative stress, which consequently causes DNA damage. [ABSTRACT FROM AUTHOR]

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Background: Within the Open Biological and Biomedical Ontology (OBO) Foundry, many ontologies represent the execution of a plan specification as a process in which a realizable entity that concretizes the plan specification, a "realizable concretization" (RC), is realized. This representation, which we call the "RC-account", provides a straightforward way to relate a plan specification to the entity that bears the realizable concretization and the process that realizes the realizable concretization. However, the adequacy of the RC-account has not been evaluated in the scientific literature. In this manuscript, we provide this evaluation and, thereby, give ontology developers sound reasons to use or not use the RC-account pattern. Results: Analysis of the RC-account reveals that it is not adequate for representing failed plans. If the realizable concretization is flawed in some way, it is unclear what (if any) relation holds between the realizable entity and the plan specification. If the execution (i.e., realization) of the realizable concretization fails to carry out the actions given in the plan specification, it is unclear under the RC-account how to directly relate the failed execution to the entity carrying out the instructions given in the plan specification. These issues are exacerbated in the presence of changing plans. Conclusions: We propose two solutions for representing failed plans. The first uses the Common Core Ontologies 'prescribed by' relation to connect a plan specification to the entity or process that utilizes the plan specification as a guide. The second, more complex, solution incorporates the process of creating a plan (in the sense of an intention to execute a plan specification) into the representation of executing plan specifications. We hypothesize that the first solution (i.e., use of 'prescribed by') is adequate for most situations. However, more research is needed to test this hypothesis as well as explore the other solutions presented in this manuscript. [ABSTRACT FROM AUTHOR]

Lithography variation presents one of the biggest challenges for photonic component optimization, especially for fabless designers. Lithography prediction models are a crucial tool for minimizing the necessary number of fabrication iterations for a device's optimization. This paper presents one of these models specifically adapted for the contra-directional coupler structure. Through the experimental characterization of devices with a specific range of design parameters, it was possible to observe how the lithography process impacts their performance. A correction model based on effective refractive index variation and its impact on the Bragg condition of the structure was developed to predict the performance variation of a device based on the expected design variation induced by fabrication. The contra-directional couplers fabricated at CORNERSTONE foundry show a tendency to be redshifted as the gap decreases, due to an increase in waveguide width as a result of a diffraction-limited lithography process. Based on these and other findings, it was possible to correlate the design parameters to the posterior fabricated structure and ultimately predict the expected experimental response. [ABSTRACT FROM AUTHOR]

Controlling large-scale many-body quantum systems at the level of single photons and single atomic systems is a central goal in quantum information science and technology. Intensive research and development has propelled foundry-based silicon-on-insulator photonic integrated circuits to a leading platform for large-scale optical control with individual mode programmability. However, integrating atomic quantum systems with single-emitter tunability remains an open challenge. Here, we overcome this barrier through the hybrid integration of multiple InAs/InP microchiplets containing high-brightness infrared semiconductor quantum dot single photon emitters into advanced silicon-on-insulator photonic integrated circuits fabricated in a 300 mm foundry process. With this platform, we achieve single-photon emission via resonance fluorescence and scalable emission wavelength tunability. The combined control of photonic and quantum systems opens the door to programmable quantum information processors manufactured in leading semiconductor foundries. Integrating tunable quantum emitters with commercial photonic circuits is promising for quantum information applications but remains a challenge. Here the authors report integration of InAs/InP microchiplets containing quantum dot single photon emitters into a large-scale foundry silicon platform. [ABSTRACT FROM AUTHOR]

Present hectic times do not allow the foundrymen to test various modifications of gating system in real production due to lack of time and efficiency of production phase. When testing of tens or hundreds of modifications is needed, simulation software MAGMA5 and its optimization procedure comes into place. This article deals with choosing the best design of gating system which will ensure the filling of the sprue as soon as possible together with possible shortening of pouring time on Disamatic line. Soonest filling of the sprue will ensure that no air is entraped in the molten metal which is entering the cavity of the mold and no air bubbles would occur in the final casting after pouring. With this goal achieved, foundry can secure the production of castings. There is a big chance chance to decrease the pouring time of the mold, which will make the production more effective. [ABSTRACT FROM AUTHOR]

Relying on scrap rates alone to assess process control in the foundry can be deceiving. Depending on the inspection method used, it is possible to sort grossly non-conforming parts, while still allowing a wide window of acceptance, masking a process that is out of control. Modern methods of acoustic resonance testing (ART) allow for detailed data logging of both part weight and resonant frequency peak data. Monitoring these two factors at the lot level can give foundry managers insight into how consistent their process is both within a single date code and across multiple date codes. The information collected during quality testing can and should be combined with statistical information gathered at the front of the foundry (design, tooling, molding, inoculation, pouring, cooling, and shakeout) and used to adjust the process to achieve smaller data spreads and more consistent and repeatable process control. Once a process is deemed to be under control, consideration should be given to monitoring the defined specification limits and subsequent control limits using statistical trend analysis as a means for ensuring a process is not approaching a condition in which the opportunity for quality issues can arise. [ABSTRACT FROM AUTHOR]

Organically-bound foundry cores are substituted by inorganically-bound cores increasingly. This trend is due to regulatory efforts, workplace safety issues, and increasing costs for waste deposits. Changing the binder system reduces the emissions to mostly water vapor, solving health and safety issues. Yet, the difference in the behavior of the gas phase, namely, the condensation potential of water, changes the casting process drastically. In contrast with the continuous generation and discharge of combustion products in the case of organic binders, water accumulates within the foundry core. Only once the cold spots of the core reach boiling temperature noteworthy amounts of vapor are created, increasing the chance for gas defects of the cast parts. Countermeasures have to be taken when designing the core's geometry. We conducted the following research to improve the understanding of core gas release and its interactions with the foundry core's binder content and storage conditions. Both binder content and relative humidity during storage were varied in three steps. Their influence on the core gas amount, time of gas generation, and gas permeability of the cores were investigated. The experiments were performed in the institute's Induction Analysis Furnace and an aluminum melt bath. We found a strong dependency of storage humidity, further increased by increasing binder content on the gas amount and time of the gas release. [ABSTRACT FROM AUTHOR]

The evaluation of mold properties is crucial in the foundry industry to ensure efficient and high-quality casting production. This study focuses on the assessment of mold properties using silica sand, copper slag, and their mixture as molding materials in the sodium silicate, CO2 (carbon dioxide) chemical binder process. The properties investigated include mold hardness, permeability, and compressive strength. The aim is to evaluate their suitability and performance in comparison with traditional molding materials. The results indicate that a mixture of 6% sodium silicate and 15 sec of CO2 gas passing is highly effective in achieving optimum mold properties for both slag and sand molds. These properties remained stable even after prolonged exposure to different weathering conditions, highlighting the durability of the molds. Furthermore, the study revealed that the combination of sand and slag yields mold properties that lie between those of the pure ingredients. Specifically, a mixture comprising 80% sand and 20% slag exhibited the most desirable properties. Additionally, investigations were conducted using a 20% sand and 80% slag mixture, which demonstrated improvements in mold properties. In terms of material substitution, the evaluation of mold properties using the CO2 process showed that copper slag displayed similar characteristics to sand. This finding suggests that copper slag can serve as a suitable alternative to partially or fully replace silica sand in mold-making applications. [ABSTRACT FROM AUTHOR]

The foundry industry is responsible for the production of several potentially polluting and hazardous compounds. One of the major sources of pollution is the use of organic binders for the manufacturing of sand cores and sand moulds. To address this problem, in recent years, the use of low-emission products, known as inorganic binders, has been proposed. Their use in ferrous foundries, otherwise, is limited due to some problematic features that complicate their introduction in the manufacturing process, as often happens when a breakthrough innovation is introduced. In light of this, the aim of this work is to provide a Green Innovation Practice (GIP) to manage the introduction of green breakthrough innovations, as previously described, within an existing productive context. This practice was applied to better manage the experimental phase of the Green Casting Life Project, which aims to evaluate the possibility of using inorganic binders for the production of ferrous castings. After describing the state of the art of GIPs and their application in manufacturing contexts, the paper described the proposed GIP and its application to a real case consisting of testing inorganic binders in a ferrous foundry. [ABSTRACT FROM AUTHOR]

Environmental and work safety aspects necessitate a radical change in the foundry industry. Organic binder systems for foundry sand cores create toxic combustion products and are, therefore, more and more often substituted by inorganic binder systems. While providing an environmental advantage by mainly releasing water vapor, inorganic binder systems impose new challenges for the casting process. The gas release of inorganically-bound foundry cores can lead to increased gas porosity in the cast parts and thus to high scrap rates. The present work aims to gain more understanding of the gas generation and transport in inorganic sand binder systems. We developed a test stand to measure the temperature-dependent core gas release in inorganically-bound foundry cores and their gas permeability. Samples were prepared in a core blowing process and analyzed using the test stand. The measurement results are in good agreement with validation experiments and existing literature. [ABSTRACT FROM AUTHOR]

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Foundries, to the same extent today as in the past, represent one of the strategic branches of all industry. In fact, all aspects of modern life depend on the casting and production of brake discs, medical implants, marine engines, and even aircraft components like turbine blades. Foundries provide supplies to all sectors of modern industry, including automotive, aircraft, medicine, power generation, etc. The Slovak economy largely depends on the automotive industry for which casting is necessary. Cast components are used not only for engines, chassis, and drives but also in vehicle bodies. This article reports information on the current number of foundries in Slovakia, the number of produced casting tons and melting methods, the casting techniques in various foundries, and the types of cast metals. It considers the income of individual foundries, the impact of the economic situation, and assumptions regarding further development. [ABSTRACT FROM AUTHOR]

The present paper describes a comparison of the efficiency of different types of rotors used in the refining of aluminium melt at a foundry degassing unit (FDU). Physical modelling was used to obtain data for six different rotor types under defined experimental conditions. In order to evaluate the data from the physical model, an evaluation method based on the interpolation of degassing curves was developed in such a way that the resulting characteristic can be expressed by a single parameter. Using the new methodology, the datasets were replaced by a single dimensionless parameter, a, which characterizes the rotor performance at a given gas flow rate. Based on the comparison of these performance parameters, it was possible to mutually compare the rotor efficiency depending on the selected conditions. The comparison is also demonstrated on the expected degassing time to a certain required concentration. Based on the physical model results, the study found that rotor D had the highest degassing efficiency, followed by rotors F and A. Rotors B and E had similar efficiency at a flow rate of 17 Nl·min−1. However, rotor B showed better efficiency at higher inert gas flow rates (19 and 21 Nl·min−1), while rotor E showed better efficiency at lower flow rates (13 and 15 Nl·min−1). [ABSTRACT FROM AUTHOR]