Al含量对Pb-Al合金耐腐蚀性能的影响

Effect of Al content on the corrosion resistance of Pb-Al alloys

利用盐雾腐蚀实验,研究铝(Al)含量对铅铝(Pb-Al)二元合金耐腐蚀性能的影响.试样腐蚀后的重量损失反映合金的耐腐蚀性能,当Al的含量(指质量百分含量,下同)为0.05%和0.10%时,Pb-Al合金的失重较小,说明其耐腐蚀性能比纯铅有明显提高.进一步提高Al含量至0.15%,Pb-Al合金的耐腐蚀性无明显改善.利用光学显微镜观察了腐蚀后显微形貌的变化,Al的含量为0.05%和0.10%时,测试面的腐蚀沟和点蚀坑数量少且尺寸较小,而当Al含量为0和0.15%时,腐蚀沟和点蚀坑的数量和尺寸均较大,此时合金的耐腐蚀性能也相对较差.

Salt spray corrosion tests （SSCT） were utilized for evaluating the effect of Al content on the corrosion resistance in Pb-Al binary alloy. By masses the masses before and after SSCT, the mass lost was obtained which reflected the corrosion resistance. When Al contents were 0.05 % and 0.10 %, the corrosion resistance was optimized compared with pure Pb. Under the condition of increasing the Al content to 0.15 %, no apparent improvement of corrosion resistance was observed. The optical microscope was used for observing its mi- crostructure. When the content of Al was 0.05 % and 0.10 %, the number and size of gully and pit etching de- clined compared with pure Pb. However, when the Al content increased to 0.15 %, the gully and pit etching were enlarged both in number and size without obvious improvement in its corrosion resistance.