【摘要】 耐海水腐蚀低合金铸铁(HD铸铁)是在普通灰铸铁(HT200)的基础上加1%~2%合金元素及变质剂而成,其相对腐蚀率可达原铸铁的5倍以上,牌号可达HT250.用稀土镁硅铁对HD铸铁做球化处理,即可得到球团状石墨的耐海水腐蚀低合金球墨铸铁(简称HDQ铸铁).用挂片法研究了它在全浸和半浸状态下的耐海水腐蚀性,并与HD铸铁做了对比.结果表明:由于HDQ球铁中含有多种合金元素,既可以提高其电极电位,又可以在铸铁表面形成牢固而致密的保护膜.同时使石墨形态从片状变为球状,与HD铸铁相比,HDQ球铁的耐海水腐蚀性能提高了2.4倍.更多还原

【Abstract】 The seawater-corrosion-resistant low alloy cast iron(designated as HD-type cast iron) has been obtained by adding 1%～2% alloying elements to grey cast iron and modification treatment,and its relative corrosion rate is five times higher than original cast iron and close to that of HT250 cast iron.The seawater-corrosion-resistant low alloy cast iron with spheroidal graphite(designated as HDQ-type cast iron) has been obtained by means of rare earth ferrosilicomagnesium spheroidizing.The seawater corrosion resistance of the HDQ-type cast iron under both whole-soaking and half-soaking conditions was investigated and compared with that of the HD-type cast iron.The results show that due to the addition of some alloying elements,the electrode potential of the HDQ-type cast iron gets increased,and the compact and adhesive protection film forms on the surface of the cast iron.Compared with the HD-type cast iron,the seawater corrosion resistance of the HDQ-type cast iron increases 2.4 times because the morphology of graphite has transformed into sphericity from flake.更多还原