The continuous industrial development that occurs worldwide generates the need to develop new materials with increasingly higher functional properties. This need also applies to the basic material for electricity purposes, which is copper. In this article, we carry out studies on the influence of various alloying elements such as Mg, In, Si, Nb, Hf, Sb, Ni, Al, Fe, Zr, Cr, Zn, P, Ag, Sc, Pb, Sn, Co, Ti, Mn, Te and Bi on the electrical and mechanical properties of ETP-grade copper. The research involves producing copper alloys using the gravity die casting method with alloy additions of 0.1 wt.%, 0.3 wt.% and 0.5 wt.%. All resulting materials are cold-worked to produce wires, which are subsequently homogenized and annealed. The materials produced in this manner undergo testing to determine their specific electrical conductivity, tensile strength, yield strength, elongation and Vickers hardness (HV10 scale).

Today’s world is a place where lack of electrical energy would be unimaginable for most of society. All the conductors in the world, both aluminum and copper, have their origin in various types of casting lines where the liquid metal after crystallization is being processed into the form of wires and microwires. However, the efficiency of the continuous casting processes of metals and the final quality of the manufactured product strictly depend on the design of the used crystallizers, the materials used during its production and its quality. Research conducted in this paper focuses on the latter, i.e., external surface quality of the graphite crystallizer at the place of contact with the primary cooling system. In order to quantify its influence on the continuous casting process numerical analyses using the finite element method has been conducted, which results have been further confirmed during empirical tests in laboratory conditions. It has been proven with all of the proposed methods that the temperature of the obtained cast rod is closely linked to the aforementioned surface quality, as when its roughness coefficient surpasses a certain value the temperature of the obtained product increases almost twofold from approx. 150–170 °C to 300–320 °C. These values might influence the quality and final properties of the cast rod, the susceptibility to wire drawing process and possible formation of wire drawing defects and therefore be of much importance to the casting and processing industry.

Constant tendency toward the improvement of the material properties nowadays creates opportunities for the scientists all over the world to design and manufacture new alloys almost every day. Considering the fact that companies all over the world desire alloys with the highest values of mechanical properties often coexisting with a reasonable electrical conductivity made it necessary to develop new materials based on Cu, such as CuMg alloys. However, before such new material may be mass produced it must undergo a series of tests in order to determine the production technology, its parameters and influence on the chemical composition, microstructural properties, and both mechanical and physical properties of CuMg alloys. The research tests have shown that with the increase of the casting feed the Brinell’s hardness of each material slightly increases (by 5 HB2.5/62.5). There is little to none impact of the casting feed on the electrical conductivity, values of which are between 20.6 and 21.4 MS/m (around 40% IACS-International Annealed Copper Standard) depending on the Mg content. The conducted scanning electron microstopy (SEM) analysis has shown that the magnesium precipitations are evenly distributed among the volume of the alloy, however, a significant difference in the density and shape of the Cu + Cu₂Mg aggregates was noticed regarding various casting feed. Static compression test proved that these alloys may be subjected to strain hardening as the hardness of the material after compression increases by approximately 40 HB2.5/62.5.

The dynamic increase in copper and copper alloy use is closely associated with the search for cathode copper substitutes in various production processes. Within the article, research was carried out on copper scraps in the form of worn-out railway catenaries, which were originally produced from Cu-ETP copper. This article assesses the industrial potential of this kind of scrap for direct use in modern production technologies of copper alloys. However, due to its characteristics, resulting from many years of wear and potential exposure to surface pollution, the assessment of potential use was made based on surface contamination influence on the chemical composition of the base material after melting and solidification (simulation of traditional casting processes). Conducted research works showed that the main contaminants of used traction copper scrap are Fe, Pb, and S and also other elements in trace amounts. The amount of copper contamination detected after direct remelting of worn catenary conductor resulted in a decrease in copper conductivity to the level of 49.3 MS/m (approx. 85% IACS). Moreover, the conducted research revealed that, due to the geometrical structure of the catenary conductor, it is partially possible to recover clean copper, characterized by high electrical conductivity (58.3 MS/m) and low impurity content.

This study presents results on developing new copper alloys for electrode caps used in resistance spot welding (RSW) of galvanized steel sheets. Two copper alloys—CuCr0.7Zr0.05 and CuCr0.3Ni0.1Zr0.05—were modified with scandium (Sc) additions of 0.01 and 0.05 wt. %. Within this article, the influence of scandium content on Vickers hardness (HV) and electrical conductivity during alloy aging was investigated. In addition, the electrode life of the produced electrodes was subjected to detailed analysis. The results demonstrated that Sc modification enables an increase in hardness with only a minimal decrease in electrical conductivity. Moreover, Sc-modified electrodes exhibited a significantly reduced diffusion layer thickness in the electrode material, which led to lower degradation of the working face geometry and reduced material loss compared with commercial Cu–Cr–Zr electrodes. Mechanical testing showed that spot joints produced with the new electrodes exceed the minimum shear–tension strength requirements even after 500 welds. These results confirm that the proposed alloying approach extends electrode cap life and improves spot weld quality, supporting its application in industrial RSW.

This study investigates Cu and Sr microalloying as two mechanistically different strategies to improve the strength-conductivity balance of a modified EN AW-6082-type Al-Mg-Si alloy for load- and current-carrying railway traction components. A Si-rich base composition (AlMg0.6Si1), selected from a prior Mg/Si optimization, was produced by metallurgical synthesis and then alloyed with Cu (0.4 wt.% and 0.6 wt.%) or Sr (0.02 wt.% and 0.05 wt.%). After casting, the materials were subjected to homogenization/solution treatment followed by artificial aging at 170–200°C for up to 24 h to map precipitation-response kinetics. Hardness and electrical conductivity were measured in the as-cast condition, after solution/homogenization, and throughout aging. The results show that Cu additions increase peak hardness but reduce conductivity, whereas Sr provides a measurable increase in hardness with a much smaller penalty in conductivity. The systematic time-temperature dataset enables a quantitative comparison between Cu and Sr modifications and identifies aging conditions that maximize the hardness-conductivity trade-off.