退火处理对含铒Al-6Mg-1Mn铝合金组织和性能的影响

研究了不同稳定化退火工艺下,热挤压含铒高镁铝合金板材的力学性能和耐蚀性能,通过优化稳定化退火工艺获得了热挤压含铒高镁铝合金板材稳定化工艺窗口。结果表明,热挤压含铒高镁铝合金板材在260～270 ℃退火,随稳定化退火时间的延长,耐蚀性能达到不敏感区;经人工加速敏化处理后合金的耐蚀性能仍然能够保持在介敏区,腐蚀性能改善;结合敏化后的腐蚀深度观察分析,结果显示在优化的260 ℃×16～24 h退火工艺下,合金具有良好的耐蚀性能和力学性能;通过透射电镜(TEM)对优化工艺合金微观组织进行分析,观察到晶界处无明显断续析出的β相,说明合金具有良好的耐腐蚀性能。

Effect of annealing treatment on microstructure and properties of Er-containing Al-6Mg-1Mn alloy

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.