奥氏体铸铁在内蒙古天然碱苛化烧碱液中的腐蚀性能

CORROSION RESISTANCE OF AUSTENIC CAST IRON IN NATURAL SODA AQUEOUS CAUSTIC

:本文研究了多种含镍、铜、铬的奥氏体铸铁 ,测试了它们在内蒙古天然碱苛化烧碱液中的腐蚀速度 ,用电镜分析腐蚀形态 ,并分析检测了金相组织和机械性能。奥氏体铸铁有极好的耐碱蚀性能 ,如本文Z4铸铁的腐蚀速度小于 1Cr18Ni9Ti钢 4 0倍。碱蚀形态为全面腐蚀。在一定含量范围内 ,随着镍及镍加铜含量的增加 ,耐蚀性提高、强度下降和塑性增加。球铁的强度和塑性 ,均优于灰铸铁 ,但两者的耐碱蚀性能属同一水平。研究结果提供 2种合金含量不太高 ,又有极好耐碱蚀性能的铸铁配方 。

This paper is to present the research of various types of austenic cast irons with the content of copper,nickel and chromium.The corrosion rates,microstructures and mechanical properties of the materials were tested and examined,and corrosion morphologies observed with SEM.The resistance of the materials to caustic has proved high.The corrosion rate of the Z4 sample,for instance,is 40 times lower than that of 1Cr18Ni9Ti steel.The corrosion resistance and plasticity improve,and the strength decreases,along with the content of Ni or Ni and Cu increased within reasonable ranges.Compared with gray cast iron,the strength of nodular iron is relatively great and plasticity high,the corrosion resistance of both the irons is of the same degree.The research has resulted in two formulae for austenic cast iron.By the formulae,contents of alloying elements in the irons are reasonably low,but they possess good resistance property to caustic.Therefore the result is expected to be widely applied.