Abstract
In the previous papers, the author showed that graphite in cast irons does not necessarily improve wear resistance of cast iron though it is an excellent solid lubricant. In this paper, the sliding experiment of flaky graphite cast irons, containing 2.64-3.50%C, against induction hardened 0.4%C steel was carried out under dry and lubricated conditions, in order to elucidate the effect graphite has on friction and wear characteristics depending on the amount added.
In the experimental conditions both the dry and lubricated coefficients of friction did not change, but the wear loss in the dry condition increased as the amount of graphite increased. On the other hand, the oil retaining and supplying characteristics improved by increasing the amount of graphite. From these results, it was concluded that increasing the amount of graphite in flaky cast irons as it was done in this experiment, does not improve friction and wear resistance, but improves oil supply and retention.
