Cailiao gongcheng (Apr 2021)

Aging precipitation behavior of 800 MPa grade ultra high strength aluminum alloy

  • ZANG Jin-xin,
  • XING Qing-yuan,
  • CHEN Jun-zhou,
  • DAI Sheng-long

DOI
https://doi.org/10.11868/j.issn.1001-4381.2021.000241
Journal volume & issue
Vol. 49, no. 4
pp. 71 – 77

Abstract

Read online

The hardness, conductivity and room temperature tensile test were used to study the properties of the new aluminum alloy aged at 110-140 ℃ for different time.The microstructure of the alloy was observed by transmission microscope (TEM).The results show that the optimum aging process of the new aluminum alloy is aging at 110 ℃ for 24 h.Tensile strength, yield strength and elongation are 808,785 MPa,6.9%, respectively.Aging temperature is the main factor affecting the type, density and size of precipitates.When aged at 110 ℃,the main precipitations are GPⅠ zones,GPⅡ zones and metastable η' phase. After aging at 110 ℃ for a long time (up to 96 h), GPⅠ zones and GPⅡ zones still exist stably.Compared with aging at 110 ℃, the precipitation process accelerates at 140 ℃.After aging at 140 ℃ for 4 h, no GP zone is observed, and the main precipitate phase is η'.After aging at 140 ℃ for 24 h, the main precipitates are η' phase and η phase.

Keywords