RE对高铬铸铁变质效果的研究

Study on the Effect of RE Modification Treatment on the High Chromium Cast Iron

采用对比试验的方法,考察了RE对Cr18W2高铬铸铁组织和性能的影响规律.金相观察表明:铸态未变质的高铬铸铁组织中,奥氏体含量多,碳化物呈粗大板条状分布,晶粒比较粗大;变质后残余奥氏体量明显减少,初生奥氏体显著细化,碳化物由粗大板条状向细板条状、菊花状转变.性能检测结果表明:RE变质处理可同时提高Cr18W2高铬铸铁的硬度、耐磨性和冲击韧度. 本实验条件下,加入质量分数为0.6%RE时,变质效果最好,材料的综合性能最佳.

The authors use ways of contrast experiment, the effect of the addition RE, on structure, performances of high chromium cast iron ( Cr18% , W2% ) was investigated. The results of metallographic observing show that the carbide distributes the thick lath form, the crystalline grain is more thick in high chromium casting iron without treatment; dimension obviously reduces in remaining after modified, carbide change from thick lath to detailed lath form and chrysanthemum form. The results of performance measure show that the hardness, impact toughness, wear resistance of the high chromium casting iron of Crl8W2 by RE treatment are all improved, The comprehensive performance of the material is the best when the optimum addition of RE is 0. 6%.