The invention discloses a homogeneous high-
toughness copper-
nickel-
tin alloy and a preparation method thereof, and relates to the technical field of non-
ferrous metal alloys. The
alloy comprises the following components in percentage by
mass: 12.0%-15.0% of Ni, 7.5%-9.0% of Sn, 0.01%-0.10% of Y, 0.001%-0.005% of B and the balance of Cu and inevitable impurities. The preparation method comprises the steps of
vacuum induction melting matched with superaudio
electromagnetic stirring, homogenization treatment,
hot working, multi-stage
solution treatment, subzero treatment and multi-stage aging treatment. The
Spinodal decomposition structure
wavelength of the
alloy is 3-8 nm, the
grain boundary Y-rich phase size is smaller than 200 nm, the tensile strength is larger than or equal to 850 MPa, the
ductility is larger than or equal to 15%, the V-shaped notch
impact toughness is larger than or equal to 90 J / cm < 2 >, and the comprehensive performance is excellent.