Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the cor...Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the corresponding microstructures were characterized by transmission electron microscopy (TEM). The results show that the value of peak hardness is increased, while the time to reach the peak hardness is reduced under an external stress. Meanwhile, the length of S(Al2CuMg) phase is shorter and the number density of S phases is larger in the creep-aged alloy. The predominant contribution to the peak hardness can be ascribed to the GPB zones with an elastic stress.展开更多
基金Project (2009BAG12A07-B02) supported by the National Science & Technology Pillar Program during the 11th Five-Year Plan Period,ChinaProject supported by Innovative Research Team in University of Liaoning Province,ChinaProject (51001022) supported by the National Natural Science Foundation of China
文摘Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the corresponding microstructures were characterized by transmission electron microscopy (TEM). The results show that the value of peak hardness is increased, while the time to reach the peak hardness is reduced under an external stress. Meanwhile, the length of S(Al2CuMg) phase is shorter and the number density of S phases is larger in the creep-aged alloy. The predominant contribution to the peak hardness can be ascribed to the GPB zones with an elastic stress.