Microstructure and Properties of Cu-Fe-Cr-Ag Alloy Prepared by Directional Solidification and Upward Continuous Casting

A Cu-Fe-Cr-Ag alloy was prepared by directional solidification (DS) and upward continuous casting (UCC) to study the effect of different casting methods on the structure and properties of Cu-Fe-Cr-Ag. The results showed that the directionally solidified Cu-Fe-Cr-Ag alloy had excellent mechanical properties and conductivity. After cold drawing and isothermal aging, the peak tensile strength (789 MPa) and peak conductivity (65.5 pct IACS) of directionally solidified Cu-Fe-Cr-Ag alloy were 21 MPa and 4.7 pct IACS higher, respectively, than those that of the upward continuously casted Cu-Fe-Cr-Ag alloy. Compared to upward continuously casted Cu-Fe-Cr-Ag alloy, the Fe dendrites in directionally solidified Cu-Fe-Cr-Ag alloy were much finer, more uniform, and arranged along the direction of the magnetic field. Cu and Ag formed a Cu-Ag eutectic structure at the edge of the directionally solidified Cu-Fe-Cr-Ag alloy rod. After multi-stage thermomechanical treatment, Ag was mainly distributed around the material and formed a structure similar to Ag-clad Cu. The directionally solidified Cu-Fe-Cr-Ag alloy had a smaller lattice constant and finer Fe fibers. The small lattice constant and Fe fibers and the special distribution of Ag lead to the excellent comprehensive performance of the directionally solidified Cu-Fe-Cr-Ag alloy.