关键词: 铒, Al-Mg-Mn合金, 晶间腐蚀, 稳定化热处理, 力学性能

Abstract: Mechanical properties and corrosion resistance of erbium-containing high magnesium aluminum alloy sheet were studied under different stabilization annealing process, and the stabilization annealing process was optimized to obtain the stabilization process window of erbium-containing high magnesium aluminum alloy sheet. The results show that the corrosion resistance of the hot extruded erbium-containing high magnesium aluminum alloy annealed at 260-270 ℃ reaches the insensitive zone with the extension of the stabilization annealing time. After sensitization treatment, the corrosion resistance of the alloy deteriorates to the insensitive zone and its corrosion resistance is improved. Combined with the observation and analysis of the corrosion depth after sensitization, the results show that the alloy has good corrosion resistance and mechanical properties under the optimized process of annealing at 260 ℃ for 16-24 h. The microstructure of the optimized alloy is analyzed by means of transmission electron microscope (TEM). No evidence of β phase precipitation continuously at grain boundary is observed, which proved that the alloy can offer good corrosion resistance.

Key words: Er, Al-Mg-Mn alloy, intergranular corrosion, stabilization heat treatment, mechanical properties