The conclusion is that the size of the coefficient of friction and the amount of abrasion are proportional to some extent. Abrasion resisting quality is the best between two same pearlitic cast irons and for a high temperature the use of a pair between mottled cast irons is the best. No good pairing is to be found between two different types of cast irons. The composition of a high chromium cast iron that may be recommended as a satisfactory material is :
         C       Si     Mn     Cr      P       S
        3.0    1.3    0.7    0.8    0.2    0.1
          Brinell Hardness 240-260.