纳米改性对含碳化物等温淬火球墨铸铁磨球金相组织的影响

Nano-modification effect of microstructure of CADI grinding ball

针对大型半自磨机现用磨球磨耗高、破碎率高的现状,研究了纳米改性和高温预处理对含碳化物的等温淬火球墨铸铁磨球金相组织的影响。实验结果表明:随着纳米改性剂加入量的增加,石墨球趋向圆整化、细小化和分布均匀化;碳化物趋向细小化和分布均匀化;高温预处理使碳化物数量减少,边界钝化,短杆状向球形过渡。优化后的金相组织细小均匀,对提高磨球的耐磨性及抗破碎能力极为有利。

According to the high metal consumption of large-scale semi-autogenous grinding (SAG) system,the modification effect of nano-modification technique on the microstructure of carbidic austempered ductile iron (CADI) grinding ball have been investigated.The results indicate that with the increase of the nano-modifier,the size of the graphite ball in CADI grinding ball is reduced,circularity increased,the number of graphite spheres are increased;similarly the carbide has higher dispersion degree,finer size.High-temperature pretreatment reduce the number of carbides,passivate boundary,transform short rods into round.The optimized microstructure is fine and uniform,which is very beneficial to improving abrasion resistance and crushing resistance of grinding balls.