Themain working method of cast ball is Martensite and Carbide,only when the composition of Cr is >10%, the eutecticcarbide  turns to be (Fe,Cr)7C3, this microstructure is greathard and tough, using cast grinding media would improve theproductivity and cut the cost about 15%-30% comparing with forgedand low chrome grinding media, more and more clients, like gold mine in Africa, Canada,asBHP,RioTinto would like to prefer high chrome grindingmedia.