The invention provides a high-strength weak-texture Cu-Ni-Si
alloy and a preparation method thereof.The preparation method comprises the following steps that a Cu-Ni-Si
alloy block is sequentially subjected to first-stage cryogenic multidirectional
forging, first aging treatment, second-stage cryogenic multidirectional
forging and second aging treatment, and the high-strength weak-texture Cu-Ni-Si
alloy is obtained. According to the scheme, a two-step cryogenic multidirectional
forging and two-stage aging
composite process is adopted, multidirectional twin variants are activated in the forging process, the twin
crystal-
dislocation interface density is improved, and high-density
nucleation sites are provided for a precipitated phase; the two-stage aging promotes a precipitated phase to be uniformly dispersed and precipitated, grain refinement and
precipitation strengthening
collaboration are achieved, and the strength is remarkably improved while the
high conductivity is kept; the multidirectional forging can also weaken the texture, randomize the
grain orientation, eliminate the
anisotropy, ensure the consistency of mechanical properties in all directions, reduce the
cracking risk and prolong the fatigue life.