The invention discloses a high-performance Al-Mg-Si
alloy and a preparation method thereof. The
alloy is composed of the following components in percentage by
mass of 0.50 to 0.85% of Mg, 0.80 to 1.30% of Si, 0.10 to 0.35% of Fe, 0.03-0.25% of Ti, 0.03-0.30% of Zr, smaller than or equal to 0.15% of the sum of inevitable impurities and the balance Al. The
alloy preparation method is a short-processsub-rapid solidification cast-rolling preparation method and comprises the five steps of alloy
smelting, water-cooling
copper roller cast-rolling, multi-pass cold rolling,
solid solution heat treatment and
artificial aging. The preparation method has the advantages that a formed Al-Ti-Zr
ternary phase effectively inhibits abnormal growth of
crystal grains in the Al-Mg-Si alloy, the
thermal stability of the alloy is remarkably improved, the distribution and the size of a precipitated phase are improved, and
precipitation strengthening is improved; a
supersaturated solid solution Zr element isintroduced to participate in the nano Mg2Si phase
precipitation process through sub-rapid solidification cast rolling, the aging dynamics is promoted, and the age hardening response is improved; and after
artificial aging, alloy grains are uniform and fine, the yield strength is high and reaches 312 MPa, and meanwhile high
plasticity is kept. According to the preparation method, the technologicalprocess steps and time are shortened, the quality of a plate strip is high, and the yield is high.