Details

Autor(en) / Beteiligte

• Li, Zhi Hui
• Wen, Kai
• Huang, Shu Hui
• Liu, Hong Wei
• Xiong, Bai Qing
• Yan, Li Zhen
• Zhang, Yong An
• Li, Xi Wu
• Yan, Hong Wei

Titel

Effect of One-Step and Two-Step Aging Treatments on Microstructure and Properties of an Al-9.0Zn-2.0Mg-2.0Cu Alloy

Ist Teil von

• Materials science forum, 2018-12, Vol.941, p.949-954

Ort / Verlag

Pfaffikon: Trans Tech Publications Ltd

Erscheinungsjahr

2018

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Aging treatments of an Al-9.0Zn-2.0Mg-2.0Cu alloy, which belongs to high strength aluminum alloy widely used in aerospace industry, are investigated by various techniques, including hardness, electrical conductivity, mechanical properties, transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). The result shows that hardness and conductivity for one-step aging treatment increase with aging time prolongs while those for two-step aging treatment exhibit increment and decrement, respectively. Besides, the ultimate tensile strength (UTS) and yield strength (YS) for one-step and two-step aging treatments show slow increase and obvious decrease, respectively. Based on these, typical T6 and T76 aging regimes are extracted for microstructure observation. The matrix precipitates for the T6 alloy have small size and dispersive distribution while that for the T76 alloy has big size and sparse distribution. The grain boundary precipitates for both exhibit discontinuous distribution and the T76 alloy has larger size and broader precipitate free zones. The selected area diffraction patterns and HREM observations reveal that main precipitates for the T6 alloy are GPI zone, GPII zone and η' phase while for the T76 alloy are η' phase and η phase.