在薄壁铸件中获得无游离渗碳体和铁素体基体的稀土球铁的关键是高碳过共晶原铁水。
Therefore, in thin section castings, for eliminating eutectic carbides and obtaining ferritic matrix, melts treated by re need high carbon content and hypereutectic composition.
为改善球铁磨球的显微组织及性能，球铁成分应控制在共晶或稍过共晶处。
In order to improve the micro-structure and the properties, the components of the nodular cast iron ball should be controlled in the point of eutectic or hyper-eutectic near the point of eutectic.
应用推荐