Abstract
Wear characteristics, microstructure and impact values of austempered ductile iron (ADI) containing chromium and vanadium were investigated. By the addition of Cr and V eutectic carbides appeared in the matrix and the number and area fraction of graphite nodules decreased. Retained austenite was increased remarkably by the addition of Cr and the bainitic structure became finer by the addition of V. Sliding were rate of the ADI containing Cr and V was very low as compared with unalloyed ones. This high wear resistance was supposed to be due to the reduced scratching and adhesive wear caused by hard carbides dispersed in the matrix. Abrasive wear resistance of the ADI containing Cr and V was also superior to FCD50, S53C and unalloyed ADI, but inferior to SKD11. The latter fact is considered to be caused by graphite nodules broken off in collision with abrasive particles. Impact values of the ADI containing Cr and V were 40 to 50 percent of those of the unallyed ones.
