Si、Ni元素对兆瓦级风电球铁件低温性能的影响

为了分析Si、Ni两种元素对兆瓦级风电球铁铸件低温性能的影响，对Si含量为1.9%~2.5%的球墨铸铁做了-20℃的低温冲击试验，并对QT350-22L做了-80℃至-20℃的低温冲击试验.与前人在QT350-22L中加入0.1%~1.0%Ni元素的-20℃冲击试验结果进行对比，结果表明，Si元素的含量是影响风电球铁件低温性能的主要因素，不建议采用加入Ni元素的方法来提高其低温性能；兆瓦级风电球铁铸件的合金成分中Si含量控制在2.1%~2.3%这个范围内时，其性能可以达到使用需求；在一定范围内，Si含量越低，兆瓦级风电球铁铸件的低温冲击性能越好，但其低温冲击性能对温度也越敏感.

Influence of Si and Ni elements on low-temperature property of ductile iron castings for MW wind power generator

In order to analyze the effect of Si and Ni elements on the low tempareture property of ductile iron castings for MW wind power generator, the low tempareture impact tests for ductile iron with Si content of 1.9%~2.5% were carried out at -20℃ and the low tempareture impact tests for QT350 22L were performed at temperatures from-20 to -80℃. In addition, the comparison with the results of the impact tests for QT350 22L with Ni content of 0.1%~1.0% at -20℃ was also conducted. The results show that the content of Si element is the main influencing factor on the low tempareture property of ductile iron castings, and it is not suggested to improve the low tempareture property of ductile iron castings through adding Ni element. When the content of Si element in the ductile iron castings for MW wind power generator is controlled within the range of 2.1%~2.3%, the property of the castings can meet the use requirement. Within a certain range, the lower the content of Si element is, the better the low temperature impact property of the ductile iron castings for MW wind power generator is, but the larger the sensitivity of low temperature impact property to temperature is.