高铬锰铸铁复合锤头的研制

在水泥矿石的二次破碎中,用高铬钼铸铁复合锤头代替高锰钢锤头,可以提高使用寿命4—5倍,获得很大的经济效益。本项研究立足国内和地方资源。以锰代钼,使锤头仍保持良好的淬透性;以稀土加铌变质,使碳化物细化,并促使形成弥散分布的二次碳化物;同时调整热处理工艺,保证基体获得达最高硬度时的残余奥氏体量;在工艺上,通过锤工作面的激冷,控制凝固方向,使共晶碳化物垂直于工作面排列,从而有利于抗磨。通过生产性抗磨试验,证明:对于12公斤的水泥矿石破碎锤头,高铬锰铸铁锤头的使用寿命与高铬钼铸铁锤头的相当,而成本降低。为高铬铸铁的应用提供了新途径。

Development of Compound Hammers of High Chromium-Manganese Cast Iron

During the second crushing process of cement or ore,the working life of compound hammers of high Cr-Mo cast iron is five or six times as long as that of the high manganese steel,which achieves better economic re- sults.The development of compound hammers of high Cr-Mn cast iron is, in the present paper,based upon domestic and local resouces.The re- placement of Mo with Mn makes the quenching degree of the hammers still remain fine.The inoculation of Re and Nb makes the carbides refined and promotes the second carbides to be dispersed.The adjustment of the heat treatment process ensures the content of remnant austenite to get the hard- est matrix.The eutectie carbides will be verticl to the working surface by controlling the direction of solidification,which is of benefit to wear resis- tance.The results of the test in actual use show,regarding 12 kg hammers, the working life of high Chromium-Manganese cast iron is equivalent to the life of high Chrnmium-Molybdenum cast iron.In addition,the cost of the former material is somewhat decreased.The present project provided a new way for high chromium cast iron application.