材料期刊网

使用瞬态气动热实验模拟系统对超硬铝合金7A04在不同瞬态高温热冲击条件下的力学性能进行了气动热模拟和热载联合实验研究, 得到7A04在热、力学环境共同作用下的高温强度极限和承载时间等重要表征参数. 实验结果表明:超硬铝合金7A04在短时热冲击环境下的强度极限比航空材料手册中长时间恒温下测量的强度极限有明显提高, 这为航空航天材料和结构在短时高速热冲击环境下承载能力的提升和结构优化设计提供了可靠依据.

Super–hard aluminum alloy 7A04 (Al–Zn–Mg–Cu), whose ultimate strength is higher than that of duralumin, belongs to a class of aluminum alloys with highest ultimate strength tested at room temperature. As it can be utilized as structural material of various heating components such as rocket liquid storage tank and missile wing, super–hard aluminum alloy 7A04 has been widely used in the field of aerospace engineering. However, the ultimate strength and other token mechanical parameters of aluminum alloy 7A04 at transient high–temperature heating environment are still unclear to us, as these key mechanical parameters are lacking in existing strength design handbook. Experimental characterization of these critical parameters of aluminum alloy 7A04 is undoubtedly meaningful to the reliability estimation, life prediction and security design of the high–speed flight vehicle. In this paper, by combining transient aerodynamic heating simulation system and material testing machine, the high–temperature ultimate strength, loading time and oher mechanical properties of super–hard aluminum alloy 7A04 undedifferent transient heating temperature and loading conditions were investigated Experimental results revealed that the ultimate strength and loading capability of aluminum alloy 7A04 subjected to transient thermal heating were much higher than those teted in a long–time stable high–temperature environmen. The results provided substantial basis fr the loading capability improvement nd optmal design of erospace materials and stuctures subject to transient heating.