The results show that Be increases the alloy hardness and raises its aging hardening rate. The hardness of the alloy is HB140 with 0.023%Be, HB120 without Be and between their values with 0.7%Be.

• 实验结果表明 :加入 0 .；0 2 3%25Be能有效提高 7475铝合金的硬度；硬度值最高可达HB140；无铍的合金其硬度值最高不到HB12 0；含 0