工业建筑屋面用铝锰合金的腐蚀行为  

Corrosion Behavior of Al-Mn Alloys for Industrial Building Roof

作　　者：王嘉琪[1] 李莉[1] 刘婷婷[2] WANG Jiaqi;LI Li;LIU Tingting(City College of Science and Technology,Chongqing University,Chongqing 402167,China;School of Materials and Energy,Southwest University,Chongqing 400715,China)

机构地区：[1]重庆大学城市科技学院,重庆402167 [2]西南大学材料与能源学院,重庆400715

出　　处：《中国腐蚀与防护学报》2022年第4期693-698,共6页Journal of Chinese Society For Corrosion and Protection

基　　金：重庆市自然科学基金(cstc2020jcyj-bsh0035)。

摘　　要：采用金相显微镜、扫描电镜、电化学工作站和化学浸泡腐蚀等手段,研究了RE含量和冷轧+退火处理对Al-Mn-RE合金显微组织和耐腐蚀性能的影响。结果表明,Al-Mn-xRE合金中可见尺寸不等、形状不规则的共晶相;添加不同含量RE后,共晶硅数量有所增多,长条状共晶组织有所细化并逐渐转变为球状或者短棒状;当RE含量达到0.25%及以上时,合金中共晶组织开始粗化;随着含量增加,Al-Mn-xRE合金的腐蚀电位和孔蚀电位都呈现先正向移动而后负向移动、腐蚀电流密度先减小而后增大趋势;在含量为0.18%时腐蚀电位和孔蚀电位取得最大值,具有最佳的耐腐蚀性能。Al-Mn-0.18RE合金的腐蚀电位和孔蚀电位从高至低顺序都为:均匀化态>冷轧+325℃退火态>轧制态>冷轧+475℃退火态;随着RE含量的增加,冷轧+325℃退火态Al-Mn-xRE合金的腐蚀速率呈现先减小而后增加的趋势,在RE含量为0.18%时取得最小值。轧制后Al-Mn-0.18RE合金的耐腐蚀性能相较于均匀化态有所降低,但后续325℃稳定化退火处理可以改善合金的耐蚀性能。The effect of RE content and cold rolling plus annealing on the microstructure and corrosion resistance of Al-Mn-RE alloy were studied by means of metallographic microscope, scanning electron microscope and electrochemical workstation. The results show that the eutectic phases with different sizes and irregular shapes can be seen in Al-Mn-xRE alloys. With the addition of different RE content, the amount of Si containing eutectic increases, the long strip-like eutectic structure was refined and gradually transformed into spherical or short rod-like structure. When RE content reaches 0.25% or more, the eutectic structure begins to coarsen. With the increase of RE content, the corrosion potential and pore size of Al-Mn-xRE alloys increase, however, the corrosion potential of Al-Mn-0.18RE alloy shifts positively and then negatively, whilst the corrosion current density decreases first and then increases. In fact, the alloy with 0.18% RE presents the maximum corrosion resistance. The corrosion potential and pitting corrosion potential of the Al-Mn-0.18RE alloys subjected to different treatments may be ranked the following order:homogenization>cold rolling+325 ℃ annealing>rolling>cold rolling +475 ℃ annealing. With the increase of RE content, the corrosion rate of the Al-Mn-xRE alloys subjected to cold rolling and annealing at 325 ℃ decreases first and then increases, and reaches the minimum value when the RE content is 0.18%. The corrosion resistance of the rolled Al-Mn-0.18RE alloy is lower than that of homogenized AlMn-0.18RE alloy, but the corrosion resistance can be improved by subsequent stabilization annealing at 325 ℃.

关 键 词：Al-Mn-RE合金 RE含量 显微组织 电化学腐蚀 化学浸泡腐蚀 

分 类 号：TG146.2[一般工业技术—材料科学与工程]