ABSTRACT
The twin-roll strip casting (TRSC) process was introduced because of its sub-rapid solidification characteristics, and the element segregation and ageing precipitation of the Cu-6Ni-1.4Si-0.1Cr alloy were studied. The results are as follows: TRSC can effectively refine grain size and inhibit the segregation of the Cu-6Ni-1.4Si-0.1Cr alloy. Two types of precipitates are formed mainly during the ageing process: disk-shaped δ-Ni2Si and rod-shaped β-Ni3Si. The comprehensive properties of the alloy are improved, and the precipitation strengthening mechanism is either from the dislocation shearing mechanism or the Orowan mechanism in different stages of ageing. The Cu-6Ni-1.4Si-0.1Cr alloy achieves optimum performance after ageing at 350°C for 4 h, where the tensile strength and conductivity are 1112 MPa and 27.35% IACS, respectively. The Avrami equations were established for the alloy to describe the kinetics of phase transformation and electrical conductivity during ageing, and the calculated results are consistent with the experimental data.
Disclosure statement
No potential conflict of interest was reported by the author(s).