Effect of Yb additions on microstructures and properties of 7A60 aluminum alloy

• Published in: Transactions of Nonferrous Metals Society of China Vol. 18; no. 1; pp. 28 - 32
• Main Author: 方华婵 陈康华 张茁 祝昌军
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2008; State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China
• Subjects: ageing; Al-Zn-Mg-Cu alloys; Al-Zn-Mg-Cu合金; mechanical properties; stress corrosion cracking; ytterbium; 机械力学; 腐蚀性能; 镱元素; ageing; Al-Zn-Mg-Cu alloys; ytterbium; stress corrosion cracking; mechanical properties
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(08)60006-0

Al-Zn-Mg-Cu-Zr alloys containing Yb were prepared by cast metallurgy. Effect of 0.30% Yb additions on the microstructure and properties of 7A60 aluminum alloys with T6 and T77 aging treatments was investigated by TEM, optical microscopy, hardness and electric conductivity measurement, tensile test and stress corrosion cracking test. The results show that the Yb additions to high strength Al-Zn-Mg-Cu-Zr aluminum alloys can produce fine coherent dispersoids. Those dispersoids can strongly pin dislocation and subgrain boundaries, which can significantly retard the recrystallization by inhibiting the nucleation of recrystallization and the growth of subgrains and keeping low-angle subgrain boundaries. Yb additions can obviously enhance the resistance to stress corrosion cracking and the fracture toughness property, and mildly increase the strength and ductility with T6 and T77 treatments.