添加微量铍对工业7475铝合金时效硬化及析出相与基体位向关系的影响

Effect of Be on ageing hardening behavior and oriented relation between precipitated phases and matrix of 7475 aluminum alloy

采用不同的淬火时效工艺研究了不同的Be含量对 7475铝合金的硬度以及析出相与基体位向关系的影响。实验结果表明 :加入 0 .0 2 3 %Be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 .7%Be合金的硬度值处于上述两者之间。同时添加铍会加快 7475铝合金的时效硬化进程。电子衍射分析表明 :含Be的合金中 ,η′相与基体的位向关系为 (1—1—2 0 ) η′∥ (42 2 —) Al,β相与基体的位向关系为 (2 0 0 ) β∥ (2 4—2 ) Al;而不含Be的铝合金中 β相与基体的位向关系为 (111—) β∥ (6 2 —0 ) Al。

The effect of beryllium on the hardness of 7475 aluminum alloy and the orientation relation between precipitation phases and Al matrix was studied with the different aging treatment method. 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. At the same time, the oriented relation of the alloy containing Be is different from that one without Be by with TEM, that is, (1-1-20) η′ ∥(422-) Al and (200) β ∥(24-2) Al with Be, (111-) β ∥(62-0) Al without Be.