Metallurgy and Foundry Engineering
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ISSN 1230-2325
e-ISSN: 2300-8377
Issue Date
2016
Volume
Vol. 42
Number
No. 3
Description
Journal Volume
Metallurgy and Foundry Engineering
Vol. 42 (2016)
Projects
Pages
Articles
The electronic component of solid fluoride electrolytes
(2016) Palimąka, Piotr Robert; Pietrzyk, Stanisław
Solid electrolytes based on sodium cryolite are present in aluminium electrolysers as frozen crystals formed on the side walls of the carbon lining (side ledge). Their main task is to protect the lining from the effect of liquid electrolyte and ensure temperature stabilization during the process of electrolysis. On the other hand, being electrically conductive, they can reduce current efficiency. In this study, the value of the electronic component of the total conductivity of the solidified electrolytes of different compositions was determined. It was found that the highest electronic conductivity is exhibited by electrolytes containing both aluminium and calcium fluoride. However, the electronic component of the total conductivity is not high, as it only reaches 0.1–2.3 mS/cm. Its share in the total conductivity of the solid multi-component electrolytes varies and, depending on their composition, is within a range of 1–10%.
Hydrometallurgical methods of indium recovery from obsolete LCD and LED panels
(2016) Krištofová, Patrícia; Rudnik, Ewa; Miškufová, Andrea
This paper shows a review of literature data on the possibilities of indium recovery from ITO layers of waste LCD and LED displays. A short characterization of indium, its compounds, resources, production, and applications is presented. The structure and operation of LCD displays are shown. A detailed overview of the ITO leaching process is presented. Methods of indium(III) ion separation from the leachate solutions (SX, HoLLE, IX) as well as recovery of the final products (precipitation, cementation, electrowinning) are also shown.
Study on the activation of calcium montmorillonite (Ca-MMT) by sodium cations
(2016) Kurleto-Kozioł, Żaneta; Grabowska, Beata
The results of spectral research (IR, UV-Vis) on the activation process of calcium montmorillonite Ca-MMT by sodium cations are presented in this article. The modifications of Ca-MMT were carried out by a modifier in the form of sodium carbonate by keeping different times of activations. On the basis of received sodium modifiers MMT (Na-MMT) analytical cycle of research was done, including structural (IR) and spectrophotometric (UV-Vis) research, in order for the designation of ion exchange ability (CEC). There was observed that the method of processing modification (changing activation time) does not affect on ion exchange ability Na-MMT. Application of modified MMT used as a binding material in greensand will be described in the next part of our planned research.
Effect of rapid solidification aluminum alloys with different Si contents on mechanical properties and microstructure
(2016) Wzorek, Łukasz; Wiewióra, Marcel; Wędrychowicz, Mateusz; Skrzekut, Tomasz; Noga, Piotr; Wiewióra, Jakub; Sajdak, Wojciech; Richert, Maria Wiesława
Rapid solidification is a relatively new and effective way of producing ultrafine-grained UFG aluminum alloys with enhanced mechanical properties. Due to a significant cooling rate close to nearly 106 K/s, it is possible to obtain a material with grain size far below 100 nm. In the present study, RS aluminum alloys with an Si content in a range of 5–10 wt% were produced during melt spinning. As a result, materials in the form of ribbons were produced. The as-received flakes were subjected to cold pressing into cylindrical billets with a diameter of 40 mm. Hot extrusion of pre-compacted material was subsequently performed at a temperature of 450°C with a press ram speed of 3 mm/s and extrusion ratio of ? = 25. In this work, the influence of brittle phases on the mechanical properties of as-extruded rods will be examined. Both tensile and microhardness tests were performed in order to determine the mechanical properties of the obtained profiles. It has been shown that brittle-phase refinement during melt spinning significantly influences the mechanical properties of the tested materials.
Characterization of oxide layers made on aluminum alloy 7075 by different methods
(2016) Jędrusik, Mateusz; Kopia, Agnieszka; Dębowska, Aleksandra; Petrzak, Paweł; Koclęga, Damian; Kalemba-Rec, Izabela
Aluminum and aluminum alloys are now being widely used as materials for structural applications due to a number of valuable properties. Improvement in the functional and decorative properties of aluminum can be obtained by forming an oxide layer on its surface. The aim of the present study was to produce and compare the properties of oxide layers on the surface of aluminum alloy 7075 and compare their properties. The methods that were used during the study were as follows: phosphating, micro-arc oxidation, and a chemical method involving the formation of a passive layer. The layers were subjected to corrosion tests. SEM and EDS methods were used for characterization of the received results. Also, some tests on an optical profilometer were done. It was proven that the micro-arc oxidation method allowed us to obtain a layer with the greatest thickness and highest corrosion resistance.