Effects of Mn and Mg Contents on Microstructure and Properties of 5A01 High Magnesium Aluminum Alloy

Three alloys with high magnesium and aluminum were prepared by ingot metallurgy to study the effects of increase Mn and Mg contents on the microstructure and properties of 5A01 aluminum alloy, which by means of microstructure observation, room temperature tensile test, exfoliation corrosion test and anodic polarization curve test. The results show that the amount of dendrite in the alloy had not obvious change when increase the Mg content in the Al-6.13%Mg-0.48%Mn aluminum alloy by 0.5%, while the amount of dendrite decreased significantly when increase the Mn content by 0.5%. With the increase the Mg or Mn content by 0.5%, the strength of the alloy was improved, while Mn had better effect. After cold rolled and annealed at 180 ℃ for 2 h, exfoliation corrosion occurred for the 5A01 Al alloy. The exfoliation corrosion sensitivity increased and corrosion potential decreased after Mg content increased by 0.5%. Mn content increased by 0.5%, the exfoliation corrosion sensitivity decreased and the corrosion potential increased.