Application of nodular cast iron grinding ball and heat treatment technology

The systematic study of wear-resistant materials has a history of more than 100 years. Different types of wear-resistant materials, such as high manganese steel, alloy steel, nickel hard iron, low and high chromium cast iron and nodular cast iron, have all gone through the basic process of research, development and continuous improvement and improvement of production technology. In recent decades, China has made great achievements and remarkable economic benefits in the systematic research and application of wear-resistant materials such as high manganese steel strengthening, various alloy wear-resistant steels, low chromium and high chromium cast iron, ductile iron, etc. The grinding balls for ball mills account for a large proportion of wear-resistant materials. After years of development, their production processes, equipment conditions and quality control have also been greatly improved, greatly reducing the consumption and cost of vulnerable parts for users.

Through the research on Si Mn alloyed ductile iron grinding balls in recent years, the following conclusions can be drawn:

1) The surface hardness of nodular cast iron grinding balls is close to that of high chromium alloy grinding balls, but the impact toughness index is higher, which is more advantageous in the long run;

2) The production cost of nodular cast iron grinding ball is reduced by using cheaper Si, Mn and other elements to replace rare and expensive Mo, Cu and other alloy elements;

3) By controlling the spheroidizing process of the nodular cast iron grinding ball and adjusting the Si/Mn content reasonably, the matrix properties of the grinding ball can be guaranteed;

4) The selection of new environment-friendly water-based quenching medium and reasonable heat treatment process can make the Si Mn alloyed ductile iron ball have better performance indexes;

5) The practice has proved that the Si Mn alloyed ductile iron grinding balls have a good effect on large SAG mills.