铝含量对铁基合金耐液锌腐蚀性能的影响

Effect of Al Content on Corrosion Resistance of Iron-Based Alloy in Zinc Liquid

用扫描电镜(SEM)观察Fe-B-Al合金基体和腐蚀界面的显微组织,用能谱仪(EDS)分析各相的化学成分,用失重法测定合金的腐蚀速率,研究了铝含量对硼铁耐液锌腐蚀性能的影响,并用显微压痕法评定了耐蚀性较好的合金的力学性能。试验结果表明,硼铁中铝含量大于18%时,主要形成与锌液不湿润的Fe-Al金属间化合物,具有很好的耐液锌腐蚀性;少量的B富集于晶界,起净化晶界作用,提高了硼铁材料的韧性。Fe-24Al-4.2B和Fe-27Al-2.8B合金在锌液中既具有良好的耐蚀性,又具有较好的韧性,在镀锌工业中具有实际应用价值。

Effect of Al content on corrosion resistance of iron-boron alloys substrate in zinc-liquid was investigated. The scanning electron microscopy （SEM） was used to analyze the microstructures of interface between alloy substrate and corrosion spots,and the energy dispersive X-ray spectroscopy （EDS） was used to analyze the chemical composition of the phases involved in Fe-B-Al alloys. A test of examination of mechanical properties and corrosion rate of the alloys was also carried out by use of the micro-indentation method and weight-loss method respectively. The results show that the Al content is more than 18wt% in iron-boron alloys,the intermetallic Fe-Al are formed mostly, which are no wettable in the zinc-liquid,and their corrosion resistance to zinc liquid is enhanced correspondently. Meanwhile, the segregation of B at grains boundary playing as cleaner role is beneficial to improve the toughness of iron-boron alloy. The Fe-24Al-4. 2B and Fe-27Al-2. 8B alloys both with the excellent corrosion resistance to zinc-liquid and good toughness can be used prolongedly in zinc-plating industry.