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Copper and its alloys with steel, including stainless steel, are soldered using brazing materials CuAgZn and CuAg- ZnSn. They are used for making connections in heating, cooling and renewable energy sources (RES) devices. The elements used in the above-mentioned alloys affect wettability, castability, corrosion resistance, impact resistance, plasticity, stress resistance and also increase the melting point of the solder. The article presents the impact of the percentage of alloying additives covered by the EN ISO 17672 standard on performance and susceptibility to soldering brazing materials Ag44 and Ag40Sn.

CuNiSi alloys are widely used in various mechanical and electrical applications. These group of materials, due to the phenomena of precipitation hardening, are able to obtain high mechanical properties with also relatively high electrical properties. In the article authors compare two different types of products, made from the CW111C alloy i.e. rods which were continuously cast on the horizontal laboratory casting set-up (low degree of structure refinement) and rods commercially extruded with high degree of structure refinement. The presented results of experimental work characterize the tested materials in terms of their chemical composition, mechanical and electrical properties depending on the manufacturing process, as well as reveal their structures and the effect of heat treatment on the morphology of the Ni-Si precipitates.

The article presents research on the metallurgical synthesis of the CuNiSi alloy with a nickel content of 2,2 wt.% and silicon in the range of 0,8 – 1,3 wt.%. Each of the produced materials were subjected to the process of homogenization, solution heat treatment and artificial aging in order to improve the mechanical and electrical properties. Materials were directed to the chemical composition tests, Vickers hardness and electrical conductivity tests and also for microstructural tests with using scanning electron microscopy (SEM).

The article presents the research results of current cyclic thermal tests performed on enamelled aluminium wires connections, made with the use of a new type of Shark-Al quick-connectors. In particular, the main purpose of the conducted research was to analyse the effect of cyclic heating on the contact resistance change during the tests which allows to test the stability of the connections in simulated working conditions under current flow. Tests included a total of 300 thermal cycles, of which the first 200 were carried out to the 65 °C temperature measured in the connector at above the ambient temperature, and then additional 100 cycles were performed for the temperature of the connector at 140 °C (tolerance +5 °C). During the tests, the resistance of samples was monitored, which allowed to verify the correctness of performed connections.

Article presents the effect of magnesium addition to copper in the range of 0,02 – 0,5 wt. %. on the mechanical, electrical and structural properties of obtained materials. All analysed alloys were produced by horizontal continuous casting set-up in the form of 9,5 mm rods. Obtained Cu-Mg alloys were next tested for their as-cast properties via Vickers hardness analysis, electrical conductivity measurements and macrostructure observations in both cross and longitudinal section. The aim of the research was to verify the influence of the magnesium content on the properties of selected Cu-Mg alloys, which are dedicated to use in overhead railway system for contact wires and catenaries.

This article presents strain gauge tests showing the force loads in the connection system of power cables, with AlMgSi sheer bolts. Among others, the analysis of the influence of the tightening torque of the clamping unit on the distribution of forces and the evaluation of the strain in the entire system was carried out. The knowledge of the force conditions and loads in the threaded connection system allowed to develop, with the use of Finite Element Method (FEM) modelling, the optimal geometry and material of elements for the power cable connection system.

The results of the research that have been presented in this article include the analysis of basic exploitational properties of connections made with the use of new family of Shark-Al connectors, which are the first in the industry strictly dedicated for connecting the enamelled aluminium wires. In particular, the test results include the analysis of the contact resistance and tensile strength of connections prepared with the various types of connectors and various configurations of used enamelled wires. Results of this work enabled to verify the correctness of performed connecting process and also allowed to verify the connectors design.

The aim of the conducted research works which are presented in the article was to determine the mechanical and electrical properties of Cu-Mg wires obtained in cold drawing process with total deformation at the level of 95 %. Base material for the research was obtained with the use of continuous casting process which allowed to produce CuMg0.02, CuMg0.05 and CuMg0.5 cylindrical rods with 9,5 mm diameter which were next cold drawn up to 1,97 mm diameter. After the cold drawing process Vickers hardness measurements along with static tensile test and electrical conductivity analysis were performed in order to determine the evolution of castings properties as a result of the applied cold deformation.

The article presents the results of research on the metallurgical synthesis of CuCrZr copper alloys with the addition of scandium as a new material for spot welding electrodes for the resistance spot welding of Zn-coated steel sheets. The tested material was manufactured in a continuous casting process in a horizontal arrangement in the form of rod. The alloys were heat treated to determine their hardness and electrical conductivity properties. Zinc diffusion tests into the material structure were carried out on the produced castings, reflecting the conditions accelerating the wear of electrodes during resistance welding of Zn-coated steel sheets.

The modifying possibility of the commercial CuZn37 brass (M63) with nickel and silicon is being discussed throughout the article. The proposed alloy additives made it possible to improve the commercial brass properties by precipitation hardening, thus making it extremely competitive in comparison to base material. The study also discussed the conditions (temperature and time) of the metallurgical synthesis and its influence on the weight percentage of not only proposed alloy additives but also the amount of zinc loss from the commercial brass due to the evaporation during the metallurgical processes.

The recycling possibility of exploited ETP grade copper railway traction scrap has been evaluated in terms of reusing the materials of high Cu content for new traction equipment dedicated for modern railway and tram overhead lines based on CuNi2Si and CuZn37Ni1Si0,5 alloys. Firstly, the conducted research was focused on the qualitative and quantitative assessment of residual impurities of the scrap materials of carrying ropes and overhead contact lines. The main research part was the metallurgical synthesis and the impact of the said impurities on the chemical composition and selected properties of copper manufactured from scrap material.

Pure copper is one of the best conducting metals among known materials, making it the first choice for wires and microwires. However, before subjecting to metal working, the material is being manufactured in the continuous casting lines. The experimental study conducted in laboratory conditions proved that the external surface quality, and thus the contact quality with the cooling system is being responsible for the worsening or improving of the heat transfer and therefore the temperature of the crystallizer itself. The conducted study might function as sort of a guideline for the industrial process.

The current trend towards nanotechnology creates possibilities for its use in materials science as manufacturing material with extraordinary properties, and is one of the goals for scientists in this field. Carbon nanotubes in particular are promising due to their electrical, thermal and mechanical properties, which have been of interest for researchers around the world. This paper focuses on the manufacturing process of the Cu-CNT composite via powder metallurgy and KOBO extrusion process, its further cold drawing process, and electrical resistance test at an elevated temperature. As obtained data proved, the higher the CNT content the lower the electrical resistance.

Cu-Ag alloys may be used in the form of sheets for the construction of bitter type magnets. The paper presents results of laboratory studies on obtaining of ingots from Cu-(1÷7wt.%)Ag alloys, solution treatment and aging and rolling process. Has been shown influence of different heat treatment and plastic deformation on the mechanical and electrical properties. The microstructural analysis of castings and sheets with the use of scanning electron microscopy (SEM) is also presented.

The presented research work covered both metallurgical synthesis of the AlCu4,5Mg3 and the continuous casting process of casts rods with a diameter of 14 mm. The obtained cast rods were further subjected to the chemical composition tests in order to determine the homogeneity and distribution of the alloy additives. Additionally the materials were tested not only in terms of their mechanical properties in the Vickers hardness test but also in terms of their structure using light microscopy and scanning electron microscopy.

Research works presented in the article aim to determine optimal ratio of Mg and Si content in chemical composition of commercial EN-AW 6082 aluminium alloy in order to maximize mechanical properties of this material. Various amounts of Si (in the rage of 0,6-1,2 wt. %) and Mg (0,6-1,1 wt. %) along with 0,4 wt. % of Fe, 0,4 wt. % of Mn and 0,05 wt. % of Ti were metallurgically synthesised with the use of gravity die casting process which allowed to obtain 5 different castings. In the next phase of research works all alloys were subjected to mechanical and electrical properties testing in as cast temper and after performed heat treatment.