Search

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.

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.

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.

Copper-based materials for electrical purposes usually find their origin in continuous casting lines where the effectiveness of the process and the quality of the final product depends among others on the crystallization system. The paper investigates the influence of the surface quality of the crystallizer and the geometry of the cooling system on the temperature distribution throughout the copper-magnesium alloys casting process. The obtained results prove that as the contact between the crystallizer and the cooling system is worsening the temperature of the crystallizer and the cast rod increase significantly, therefore affecting the efficiency of the process.

Modern non-ferrous metal applications are faced to high requirements in terms of even distribution of the alloying elements. In general, the homogeneity of the chemical composition of the materials affect to their mechanical properties. As part of this paper the relationship between the local concentration of Mg and Si in 90 mm diameter billets from EN AW-6060 aluminium alloy and local variability of yield stress in experimental conditions which simulates technological conditions for hot metal forming processes. The phenomenon of macrosegregation remained specified for billets obtained in the technology of horizontal continuous casting, dedicated to extrusion or forging.

The article presents a material analysis for a new generation of cable screw connectors with shear bolts designed for not only 1st and 2nd class of cables but also 5tth class of aluminium and copper conductors that have not been previously supported. The set of properties of aluminium series 6xxx designated for screw connectors production has been determined. Finite Element Method (FEM) simulation of the controlled shear of the bolt at the body of the screw connector has been carried out. The repeatability of the bolt shear in the actual conditions was also conducted in order to verify the prototypes of the new generation of cable screw connectors.

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.