III 2018

Effect of molecular weight and amount of PGE on SiC-based slurries
In the present paper properties of silicon carbide slurries in manufacturing shell moulds for investment casting of aircraft turbine elements were studied. Ceramic SiC slurries with a solid concentration of 60 wt. % were applied. As a structural binder nanodispersion containing colloidal Al2O3 was used. The poly(ethylene glycol) (PGE) with molecular weight 6000, 10000 and 20000 g/mol as a rheological modificators were added at different amount: 5, 10, 15 wt. %. Characterization of SiC powder were made by: grain size by laser diffraction, Scanning Electron Microscopy (SEM) and X-Ray diffraction (XRD, XRF) methods. The properties of ceramic slurries such as: relative and dynamic viscosity, plate (plate weight test) and wax adhesion were studied by a range of techniques. These measurements were taken in laboratory conditions by 96 hours at temperature 21oC. The results shows that SiC-based slurries, nanodispersion binder and PGE meet the investment casting requirements of aircraft turbine parts and had promising properties.
Paweł Wiśniewski, Ph.D. Eng.

Physicochemical properties of glass-ceramic materials from the SiO2-Al2O3-Na2O-K2O-CaO-MgO system with barium oxide addition
Glass-ceramic materials are the subject of increasingly broader study due to the possibility of shaping their properties. These materials are obtained as a result of the suitable selection of the initial oxide composition and by suitable heat treatment. This paper presents effect of raw material composition on the physicochemical properties of glass-ceramic
materials from the SiO2-Al2O3-Na2O-K2OCaO- MgO-BaO system. Three compositions differing in the raw materials introducing selected oxides to the system were examined. Three firing temperatures: 1190, 1200, 1210°C were used. As the selected properties, roughness, gloss, whiteness in the CIELab system and flexural mechanical strength after firing were measured. Differences were observed in the phase composition, which were determined by X-ray diffraction (XRD). The characteristic temperatures, which were measured by using hot stage microscopy and optical dilatometry, also showed changes.
Karolina Kaczmarczyk M.Sc.

Development of technology for waste management created at the production of technical ceramics wares
The publication presents the method of obtaining alumina ceramic granulate in a spray dryer from waste generated during the forming of green wares. The type and amount of necessary additives were determined, which allow to obtain a regranulate with properties identical to the original granulate. The products made from it achieve the required performance.
Tadeusz Jakubiuk M.Sc. Eng.

Dining rooms of Lodz's bourgeoisie in 19th and 20th century
At the turn of the 20th century the most numerous group among the habitants of Lodz was the petty bourgeoisie which accounted 20% of its society. The proper bourgeoisie originating from this group was about 7%. Forefront of industrial families contained of: Scheiblers, Poznańscy, Geyers, Heinz, Meyers, Grochmans, Herbsts, Silbersteins, Biedermanns, Hertz, Scheiweikerts and Eitingons. Because of their social status they were able to create their own forms of etiquette. It was based not only on the behavior of western aristocracy but also contained elements taken from their families tradition. One of the most important pieces of this etiquette were broadly defined culinary issues. Social and family interactions were mainly pursued at the dining table. Therefore it was of utmost importance to pay attention to every detail of the setting where the meetings were held as well as the overall look and decoration of the dining room. This article presents the result of the research conducted on both the symbolic and material of the titular table, connected to the rooms equipment, iconography of the interiors and the living customs. It is based on the archival and iconographical materials, memoirs and prose devoted to the city of Lodz.
Łukasz Grzejszczak Ph.D.