摘要
An aluminum alloy （Al-Zn-Mg-Cu） subjected to deep cryogenic treatment （DCT） was systematically investigated. The results show that a DCT-induced phase transformation varies the microstructures and affects the mechanical properties of the Al alloy. Both Guinier-Preston （GP） zones and a metastableη′phase were observed by high-resolution transmission electron microscopy. The phenomenon of the second precipitation of the GP zones in samples subjected to DCT after being aged was observed. The viability of this phase transfor-mation was also demonstrated by first-principles calculations.
An aluminum alloy （Al-Zn-Mg-Cu） subjected to deep cryogenic treatment （DCT） was systematically investigated. The results show that a DCT-induced phase transformation varies the microstructures and affects the mechanical properties of the Al alloy. Both Guinier-Preston （GP） zones and a metastableη′phase were observed by high-resolution transmission electron microscopy. The phenomenon of the second precipitation of the GP zones in samples subjected to DCT after being aged was observed. The viability of this phase transfor-mation was also demonstrated by first-principles calculations.
基金
supported by the Fundamental Research Funds for Central Universities of China(No. XDJK2014C008)
the National Natural Science Foundation of China(No.51171156)
the Key Scientific and Technoogical Projects of Chongqing(Nos.CSTC2012GGYS5001 and CSTC2013JCYJYS5002)
