3楼回答靠谱。。。没求证呢。。。 开始以为 什么 球铁 球墨铸铁类的呢。。。

是英国的钢种牌号，老外的介绍是： the rqt range of steels have been developed for applications where high strength and outstanding toughness are necessary, such as mining and quarrying, process industry, material handling, construction and earthmoving. 国内 纪贵主编 《世界标准钢号手册（第2版）》 第850页有详细的成分介绍。

啊？都没有人搭理我，那我自己顶一下吧！

是英国的钢种牌号，老外的介绍是： the rqt range of steels have been developed for applications where ... 忒牛，能给翻译一下吗？