Interaction mechanism of elements and second phase characteristics in as-cast Cu–15Ni–8Sn–(1Al–0.1Y) alloy

In this article, the effects of Al and Y elements on the microstructure and mechanical properties of Cu–15Ni–8Sn alloy were studied. The interaction mechanism between elements is proved by first-principles calculation. The results show that the strength of Cu–15Ni–8Sn–1Al–0.1Y alloy reaches 760 MPa, and the hardness of matrix (α-Cu) and Sn-rich phase (γ) are 292.43 and 341.65 HV, respectively, which are 23.78%, 97.80% and 65.21% higher than those of Cu–15Ni–8Sn alloy, respectively. The formation of a large number of dispersed nano-scale Ni 3 Al second phase is the main reason for the great improvement of the strength of the alloy. In addition, the solid solution of Al and the formation of the Ni 17 Y 2 phase improve the hardness of the Sn-rich phase.