|Adam Bitka, Krzysztof Jaśkowiec
CADI (Carbidic ADI) - ausferritic ductile iron containing carbides - is a relatively new engineering material which exhibits excellent wear resistance and adequate impact strength. In this work the influence of two-step austempering process on selected properties of CADI cast iron was examined. Two batches of samples were initially austenitized at 900°C for 60 min. The first batch of the samples was austempered conventionally by single-step process in a salt bath at 4 different temperatures: 300, 330, 360 and 390°C for 120 min. The second batch was processed by two-step austempering process, first in a salt bath at 260°C for 10 min and subsequently in second salt bath at temperatures 300, 330, 360 and 390°C for 120 min. Results show that two-step austempering process improves impact strength and wear resistance of CADI compared to conventional heat treatment process.
Keywords: CADI, ductile iron, carbides, ausferrite, two-step austempering, impact strength, wear resistance,
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The article discusses the impact of selected operations of the casting production technological process on the workplace environment, as well as on the external environment. The casting production is associated with technological operations that may have a greater or lesser impact on the conditions at the workplace and the environment of the industrial plant. Foundry processes applied in making castings are associated with the occurrence of many hazards, e.g. pollution, contamination, noise, gas emissions and other factors harmful to health and the natural environment. Many technological processes are related to the onerous working conditions in foundries. The benefits and threats of the Lost Foam technology for making castings are presented. In recent years, the casting technology using gasified models has been widely used for making castings in the world not only made from non-ferrous alloys, but also for iron-base alloys. Complicated castings could be made, e.g. car engine heads for the automotive industry. Castings production using polystyrene models is much less energy-intensive and labor-intensive than technology using models from traditional materials.
This technology is innovative, energy-saving, and is characterized by many technical, ecological and economic benefits, and also affects the protection of the workplace environment positively.
Keywords: environment, casting technology, gasified models, polystyrene, gas emissivity,
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Andrzej Fijołek, Jagoda Ryba, Paweł Żak, Janusz Lelito
The aim of the work was to develop and model individual elements of casting technology for the casting of a ventilated brake disc using CAD program: SolidWorks, followed by printing a core using a 3D LS ONE printer from Sand Made Ltd. Next, the finished core was scanned with the 3D MetraScan 70 scanner. The virtual model obtained in this process was used to control the fidelity of print performance in relation to the object designed in the CAD program. Dimensional control designed 3D model of the core in relation to the real object was performed in Geomagic Control software. Dimensional control made the verification of dimensional deviations printed core in relation to its project in 3D CAD software - SolidWorks. The end result was ready core for casting mold, which is inserted into the mold can be used in the foundry process.
Keywords: CAD design, 3D printing, 3D scanning, mould, core,
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Emilia Wildhirt, Jarosław Jakubski, Małgorzata Sapińska, Sylwia Sitko, Jadwiga Kamińska
This article presents selected research methods related to protective coatings used for sand moulds and cores in the foundry industry. The research methodology has been divided into studies of the technological properties of sand moulds and cores with applied coatings (the measurement of hot distortion parameter after deposition of coatings onto moulds made of loose self-hardening sands with organic binders) and physico-chemical properties (viscosity) of finished coatings.
Coatings with aqueous and alcohol solvents were tested. Moulds were prepared from loose self-hardening sand mixtures with furfuryl and phenol-formaldehyde resins and were coated with water-based coatings and alcohol-based coatings.
Studies were carried out in the Department of Moulding Materials, Mould Technology and Cast Non-Ferrous Metals at the AGH Faculty of Foundry Engineering in Krakow and at the Foundry Research Institute in Krakow.
Keywords: protective coatings, viscosity, hot distortion parameter,
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The fundamental aim of the study was to obtain high-alloy granulate. The study tests many possibilities of obtaining granulate with the use of the appropriate methods. The preliminary tests with the use of small melting units as well as granulate obtaining methods (vibrations, filters of various kinds etc.) made it possible to direct the further course of the research. The elements of the test stand for obtaining metal granulate with the shape similar to a globular one were constructed and selected. The types of filters through which the melted metal should be poured to obtain the assumed effects, i.e. ones with particular fractions (e.g. the proper height from which the metal falls through the filter, the filter mesh sections, the cooling agent type) were selected. The final effect was the obtaining of a specific amount of granulate with a unified shape.
Keywords: test stand for alloy granulation, methods of obtaining granulate, high-alloy cast steel, filter,
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