The result shows that the improper handling craft for molten iron spheroidization is the main factor leading to spheroidizadon deficiency,thus its machine strength is lower.

• 其次是正火处理时,出炉温度低,促使铁素体相大量析出，导致齿圈的耐磨性能下降。为此,采取相应的措施,增强了齿圈的抗磨性。