Metallurgy and Foundry Engineering
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ISSN 1230-2325
e-ISSN: 2300-8377
Issue Date
2017
Volume
Vol. 43
Number
No. 4
Description
Journal Volume
Metallurgy and Foundry Engineering
Vol. 43 (2017)
Projects
Pages
Articles
Thixoforming of high-melting-point alloys
(Wydawnictwa AGH, 2017) Sołek, Krzysztof
Processing of steel in the semi-solid state concerns mainly continuous casting and thixoforming processes. Continuous casting is usually applied within the confines of steel making processes. Due to stringent process requirements, thixotropic forming of steel alloys has not been practically applied in industry yet. However, it is believed that this method could be used for forming selected products. Thixoforming could be treated as alternative method of production for forging techniques in the case non-plastic alloys. In this paper the method of development of globular microstructure, thixoforming process and analysis of rheological properties of selected steels were described.
Effect of test conditions on wear properties of steel-matrix composites
(Wydawnictwa AGH, 2017) Sulima, Iwona; Hyjek, Paweł
The friction coefficient and wear behavior of 316L austenitic stainless steel and 316L steel + 8vol% TiB? + 1vol% B composites were investigated within a temperature range of 20°C to 800°C. The materials were prepared by the powder metallurgy method. The wear behavior was studied by using a ball-on-disc wear tester at room temperature. The surface before and after wear tests was analyzed using scanning electron microscopy (SEM). The results indicated that the friction coefficient and wear resistance of stel-8TiB?-1B composites depend on the wear test conditions.
Influence of welding techniques on microstructure and hardness of steel joints used in automotive air conditioners
(Wydawnictwa AGH, 2017) Noga, Piotr; Węglowski, Marek Stanisław; Richert, Maria Wiesława; Zimierska-Nowak, Patrycja; Dworak, Jerzy Maciej; Rykała, Janusz
Austenitic steels belong to a group of special-purpose steels that are widely used in highly aggressive environments due to their enhanced anticorrosive behavior and high mechanical properties. The good formability and weldability of these materials has made them very popular in automotive AC systems. This study presents the results of hardness tests and microstructure observations on plasma- and laser-welded joints. The examined joints consisted of two different stainless steel components, i.e., a nipple made from corrosion-resistant AISI 304 steel and a corrugated hose made from 316L steel. Microplasma welding was carried out on a workstation equipped with an MSP-51 plasma supply system and a BY-100T positioner. The laser-welded joint was made on a numerically controlled workstation equipped with an Nd:YAG laser (without filler material) with 1 kW of maximum power, the rotational speed of the welded component was n = 4 rpm. Microstructural observations were performed using a scanning electron microscope and an optical microscope. Vickers hardness was measured with a hardness tester. The obtained results proved that both the microplasma- and laser-welded joints were free from any visible welding imperfections. In the micro areas of the austenitic steel weld, crystals of intercellular ferrite appeared against a background of austenite. The crystallization front (depending on the welding technology) was running from the fusion line towards the weld axis. The grain size depended on the distance from the fusion line.
Influence of corrosion on mechanical properties and microstructure of 3xxx, 5xxx, and 6xxx series aluminum alloys
(Wydawnictwa AGH, 2017) Ziobro, Grzegorz; Richert, Maria Wiesława; Wiewióra, Marcel
Growing demands imposed on passenger car producers concerning the reduction of exhaust emission to the environment are forcing a search for new materials and design solutions. One of the most-important factors that can reduce this emission is the low mass of a vehicle, leading to a decrease in its average fuel consumption. A reduction in weight can be obtained by the use of aluminum elements instead of steel, e.g., in air conditioning pipes, decreasing the specific weight of the construction by nearly three times. In the present study, the influence of the SWAAT corrosion test on A/C piping made from 3xxx, 5xxx, and 6xxx series aluminum alloys was investigated. The study focused on changes in the mechanical properties of samples before and after a SWAAT test determined by a tensile test and Vickers hardness measurements. Additionally, microstructure examinations were performed with the use of optical and scanning microscopy. Corrosion products on the surface of pipes were identified by Energy Dispersive X-ray Spectroscopy. Pipes made from the EN AW 6063 alloy revealed an almost 50% decrease in its strength properties after the tests. The largest decline in plastic properties was observed in pipes made from the EN AW 6060 alloy.
Impact of selected parameters on extraction of indium from LCD screens
(Wydawnictwa AGH, 2017) Stępień, Michał; Palimąka, Piotr Robert; Bukowska, Andżelika
Due to the minute availability of indium and its crucial importance to the world economy, it is necessary to find alternative sources of this metal. As a large proportion of indium production is consumed for the purpose of LCD screen manufacturing, it seems reasonable to investigate their recycling leading to the recovery of this metal. The present work investigates the impact of time, temperature, and the concentration of sulfuric acid on the effectiveness of indium extraction from milled LCD panel glass scrap originating from portable computers manufactured between 2005 and 2012. The conclusion of our research defines the optimal conditions for extraction.