Preparation of Cu–Cr–Zr alloy billets by horizontal electromagnetic continuous stirring

Abstract

The addition of Cr and Zr into the Cu base is applied to overhead contact wires and lead frames due to its high tensile stress and electrical conductivity. Results show that the length of 45 m for Cu–Cr–Zr alloy billets can be successfully prepared by horizontal electromagnetic continuous stirring. The optimised parameters on Cu–Cr–Zr billets with 87 mm diameter are as follows: the current is 50 A, the frequent is 30 Hz and the casting speed is 108 mm min−1. The rotating magnetic field (RMF) can decrease the casting temperature by 22°C. The average grain size with RMF is 1·35 mm, reduced by 55% compared to that without RMF. The tensile stress is 212 MPa, and elongation is 33%. The microstructure with RMF on non-vacuum casting is similar to that of the vacuum. At the same time, RMF makes Cr, Zr and Cu atoms uniformly distributed.