几种常用7×××系铝合金成分设计规律分析

Design rules of chemical compositions of some normal used 7 × × × series aluminum alloy

高强度7×××系铝合金是航空航天工业的主要结构材料。对常用的五种7×××系铝合金的化学成分、不同厚度的板材以及其对应的力学性能进行了对比分析。通过Thermo-Calc热力学软件计算和试验验证,分析研究了合金中的元素配比、析出相与力学性能以及淬火性能之间的关系。结论是:对于7×××系铝合金,提高合金元素添加量可以获得更多的沉淀析出相,从而提高合金的强化效果;而减少沉淀析出相的总量可以降低7×××系铝合金的淬火敏感性;减少强化效果差的析出相,获得更多有效的强化相,则既有利于提高强化效果又有利于降低7×××系铝合金的淬火敏感性。

High strength 7 x x x series aluminum alloy is the main structure material in a- viation and spaceflight industry. The corresponding relationship of chemical composition, plate thickness and mechanical property of five commercial 7 x x x series aluminum alloys has been analyzed. The relation among the alloying element burden, segregated phase, me- chanical property and quenching property has been calculated and verified by using of Ther- mo-Calc thermodynamics software. The results show that to increase, alloying element quantity can obtain more dispersed segregation phases, therefore the strengthening effect of 7 x x x al- loy can be improved; meanwhile the quenching sensitivity of 7 x x x series aluminum alloy would be decreased while decrease the segregated phases;to reduce the segregated phases with low strengthening effect can obtain more effective strengthening phases, which is in favor of both increasing the s aluminum alloy.