1972年,芬兰 Hgfors 铸造厂研制出了一种叫做 Kymenite 9805的新型球墨铸铁。几年来,芬兰国有铁路用这种材料制成闸瓦、车轮、轮箍以及拉杆等配件,安装在调车机、矿车和货车上进行了广泛的运用实验,结果证明,这种材料不但本身高度耐磨,而且与它同时使用的各种偶合件磨损程度也大大降低,因此,被认为是一种 In 1972, Hgfors foundry in Finland developed a new ductile iron called Kymenite 9805. In recent years, Finland’s state-run railway has used such materials as brake shoes, wheels, tires, tie rods and other accessories to conduct a wide range of operational experiments on shunting machines, tubs and wagons. The results show that this material not only itself Highly wear-resistant, but also with its use of the various coupling wear is also greatly reduced, therefore, is considered a