Wear resistance of high chromium -: high carbon cast irons

High chromium - high carbon experimental castings were produced using chilled moulds to study their resistance while subjected to erosive conditions. An experimental design in which the ratio of chromium over carbon equivalent, the amount of molybdenum and that of vanadium plus titanium were varied each in two different levels to obtain eight different casting conditions. The average size and volume fraction of the carbides present in the castings were determined by quantitative analysis. Samples cut from the ingots were subjected to wear in a specially designed rig that used directly reduced iron pellets as an erosive agent; the design is such that these particles impinge the samples after being impulsed by commercial purity nitrogen heated up to maintain a temperature of 550degreesC. A multi-linear statistical model was developed to relate the wear resistance of the samples. It was found that resistance to wear was related to chemical composition, in such a way that the samples that exhibit higher wear were those with the higher amount of molybdenum. It was also found that the distribution of primary carbide sizes could affect resistance to wear.