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Abstrakt

The cast alloys crystallizing in Fe-C-V system are classified as white cast iron, because all the carbon is bound in vanadium carbides. High vanadium cast iron has a very high abrasion resistance due to hard VC vanadium carbides. However, as opposed to ordinary white cast iron, this material can be treated using conventional machining tools. This article contains the results of the group of Fe-C-V alloys of various microstructure which are been tested metallographic, mechanical using an INSTRON machine and machinability with the method of drilling. The study shows that controlling the proper chemical composition can influence on the type and shape of the crystallized matrix and vanadium carbides. This makes it possible to obtain a high-vanadium cast iron with very high wear resistance while maintaining a good workability.
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Abstrakt

This preliminary study characterizes the bronze metalworking on a defensive settlement of the Lusatian culture in former Kamieniec (Chełmno land, Poland) as it is reflected through casting workshop recovered during recent excavations. Among ready products, the ones giving evidence of local metallurgy (e.g. casting moulds and main runners) were also identified. With the shrinkage cavities and dendritic microstructures revealed, the artifacts prove the implementing a casting method by the Lusatian culture metalworkers. The elemental composition indicates application of two main types of bronzes: Cu-Sn and Cu-Pb. Aside these main alloying additions, some natural impurities such as silver, arsenic, antimony and nickel were found which may be attributed to the origin of the ore and casting technology. The collection from Kamieniec was described in terms of its structure and composition. The investigations were made by means of the energy dispersive X-ray fluorescence spectroscopy (ED-XRF), scanning electron microscopy (SEM) coupled with an energy dispersive Xray analysis system (EDS) and optical microscopy (OM). In order to fingerprint either local or non-local profile of the alloys, the ED-XRF data-set was statistically evaluated using a factor analysis (FA).
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Abstrakt

The work presents experiment results from the area of copper casting technology and chosen examples of alloyed copper. At present, copper casting technology is applied in many branches of industrial manufacturing, especially in the sector of construction, communications, arms and power engineering. Alloyed copper, containing slight additions of different elements and having special physio-chemical properties, is used in a special range of applications. Copper technology and alloyed copper analyses have been presented, these materials being used for cast manufacturing for power engineering. The quality of casts has been assessed, based on their microstructure analysis, chemical content and the cast properties. During the research, special deoxidizing and modifying agents were applied for copper and chosen examples of alloyed copper; also exemplary samples were tested with the help of metallographic analysis, electrical conductivity and gaseous impurities research.
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Abstrakt

The research focuses on assessing the metal content, mainly copper, lead, iron and also silver in metallurgical slag samples from the area where historical metallurgical industry functioned. In the smelter located in Mogiła, near Krakow (southern Poland), whose operation is confirmed in sources from 1469, copper was probably refined as well as silver was separated from copper. Based on the change of chemical and soil phase content and also taking cartographic and historical data into account, considering the restrictions resulting from the modern land use the area was determined whose geochemical mapping can point to the location of the 15th century Jan Thurzo’s smelter in Mogiła near Krakow. Moreover, using the same approach with the samples of this kind here as with hazardous waste, an attempt has been made to assess their impact on the environment. Thereby, taking the geoenvironmental conditions into account, potential impact of the industrial activity has been assessed, which probably left large scale changes in the substratum, manifested in the structure, chemical content and soil phase changes. Discovering areas which are contaminated above the standard value can help to identify historical human activities, and finding the context in artefacts allows to treat geochemical anomalies as a geochronological marker. For this purpose the best are bed sediments, at present buried in the ground, of historical ditches draining the area of the supposed smelter. Correlating their qualities with analogical research of archeologically identified slags and other waste material allows for reconstructing the anthropopressure stages and the evaluation of their effects. The operation of Jan Thurzo’s smelter is significant for the history of mining and metallurgy of Poland and Central and Eastern Europe.
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Abstrakt

High prices of tin and its limited resources, as well as several valuable properties characterising Cu-Sn alloys, cause searching for materials of similar or better properties at lower production costs. The influence of various nickel additions to CuSn10 casting bronze and to CuSn8 bronze of a decreased tin content was tested. Investigations comprised melting processes and casting of tin bronzes containing various nickel additions (up to 5%). The applied variable conditions of solidification and cooling of castings (metal and ceramic moulds) allowed to assess these alloys sensitivity in forming macro and microstructures. In order to determine the direction of changes in the analysed Cu-Sn-Ni alloys, the metallographic and strength tests were performed. In addition, the solidification character was analysed on the basis of the thermal analysis tests. The obtained results indicated the influence of nickel in the solidification and cooling ways of the analysed alloys (significantly increased temperatures of the solidification beginning along with increased nickel fractions in Cu-Sn alloys) as well as in the microstructure pattern (clearly visible grain size changes). The hardness and tensile strength values were also changed. It was found, that decreasing of the tin content in the analysed bronzes to which approximately 3% of nickel was added, was possible, while maintaining the same ultimate tensile strength (UTS) and hardness (HB) and improved plasticity (A5).
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