Properties and microstructure characterisation of high-strength, high-conductivity and high-resistance to arc ablation Cu-0.6Te-0.3Cr-0.15Zr-0.008P alloy

In this paper, the intermetallic compound ZrTe2 phase is formed within a copper matrix by data-driven elemental screening. This low melting point ZrTe2 phase is uniformly and diffusely distributed within the copper matrix, which avoids the need for an energy-intensive process while providing superior resistance to arc ablation. On this basis, a novel Cu-0.6Te-0.3Cr-0.15Zr-0.008P alloy is designed and prepared, and the alloy achieves an electrical conductivity of 95.7 %IACS, a tensile strength of 302 MPa, and an elongation of 39.53% after the thermomechanical treatment. The ablation current of the novel alloy under large voltage is 31.2% lower than that of the Cu-0.6Te alloy, and the cross-sectional area of the ablation traces is reduced by 85%, which effectively illustrates the substantial improvement of the novel alloy's ability to resist arc ablation. There are ZrTe2 phases of 0.5–2 μm as well as pure Cr phases of about 5–20 nm in the alloy. The ZrTe2 phases absorbs heat through melting decomposition to achieve arc extinction, and the Cr phases pinning dislocations to promote strength enhancement. In addition, the synergistic addition of Cr and Zr plays a role in the grain refinement of the alloy, and the average size of the grains decreases from 4.2 μm to 3.1 μm, a decrease of 26%, under the same process. This novel CuTe alloy with high strength, high conductivity and high resistance to arc abrasion is easy to produce and low energy consumption, and is expected to be widely used in the new generation of high-voltage fast-charging electrical connector materials for new energy vehicles.