钇基重REMg球化剂在风电铸件中的应用

Application of Y-Base Heavy Rare Earth-Containing REMgFeSi Nodularizing Alloy to Wind-Power Castings

介绍了QT400-18AL的主箱体和QT450-10的3 MW行星架铸件的要求和铸造工艺,以及生产厚大球铁铸件必须重视的问题,试验结果显示:应用Y基重REMg球化剂生产大断面风电球铁铸件,具有较强的抗球化衰退能力,铸件的各项力学性能指标完全符合材料要求。分析Y基重REMg球化剂抗球化衰退的原因为:①重RE元素沸点高;②不会发生因返S现象而导致的球化衰退;③具有较强的抗石墨畸变能力;④充分利用了RE元素间和Mg、Ba、Ca之间互为补充的叠加作用及复合作用。

Technical requirements, casting process and the main points of the QT400-18AL grade nodular iron main case body and the QT450-10 grade nodular iron planet support was introduced. The test result showed that the heavy section wind power nodular iron castings produced by using Y-base heavy RE-Mg nodularizer have relatively strong ability to prevent nodularization degeneration, and all the mechanical properties fully met the material requirements. The reasons why the heavy RE-Mg nodularizing alloy has strong ability to prevent nodularization fading were analyzed as follows：（a）the heavy rare earth elements have high boiling point;（b） it＇s impossible to occur that the S returning from the slag to the iron melt would cause nodularization degeneration; （c）the heavy RE has relatively high ability to prevent the nodular graphite degeneration; （d）the mutual complementation effect and combination effect of the RE and Mg, Ba, Ca was fully utilized.