Effects of Si addition on mechanical, electrical and magnetic property of Cu-10Fe alloy

A series of Cu-10Fe-xSi (x = 0, 0.8, 1.6 wt%) alloys are prepared. The effects of Si content and a novel multi-stage thermomechanical treatment on the microstructure, mechanical, electrical and magnetic properties of the alloys are studied. The results show that Cu-10Fe-0.8Si alloy has greater strength, magnetic permeability and excellent electromagnetic shielding performance than Cu-10Fe alloy. After peak aging treatment (450 °C/68 h), the tensile strength, conductivity, elongation, and relative magnetic permeability of the Cu-10Fe-0.8Si alloy are 593.6 MPa, 55.66%IACS, 22.8% and 1.57 respectively. Experimental results show that the addition of an appropriate amount of Si element will form a dual-scale FeSi phase in the alloy. The large FeSi phase is formed during solidification, and its average size is 400 nm. The small FeSi phase is precipitated during aging, and the average size is 15 nm. The formation of the dual-scale FeSi phase is conducive to promoting the precipitation of Fe atoms and refining the alloy grains, so that the strength and magnetic properties of the alloy can be improved synergistically.