Effect of Ti–Zr addition on the microstructure and the arc chopping current of melt-spun CuCr ribbon

The microstructure and the arc chopping current of melt-spun Cu71Cr29 ribbon added by Ti–Zr are studied in the article. The results reveal that the melt spinning could partly restrain the liquid phase separation of CuCr alloys because it has a high cooling rate (about 106 K/s), the size of the Cr rich phase from liquid phase separation in the Cu71Cr29 microstructure can be decreased from the micron-scale to about 250 nm by using melt spinning. On the melt-spun base, alloying by Ti–Zr could further decrease the size of the Cr rich phase from 250 nm to about 100 nm. For nano-grained CuCr alloys, its lower arc chopping current is advantageous to the use of contact and the circuitry protect, its long arc trace route and high velocity of spot direction motion could mitigate the partial ablate of cathode surface and the lifetime of contact could be prolonged.