Enhancement of the Crack Resistance of Manganese Cast Irons

Abstract

We have determined the parameters of static $$(K_{IC} = 30 - 44MPa\sqrt m )$$ and cyclic crack resistance of austenitic manganese irons $$(\Delta K_{th} = 4.7 - 6.3MPa\sqrt m ,\quad \Delta K_{fc} = 35 - 44MPa\sqrt m )$$ . The results obtained were compared with literature data. High K IC values in the alloys under consideration were reached owing to the refining action of calcium. We have studied the micromechanism of fracture of these materials with the use of modern methods of investigation. We have shown that the parameters of the graphitic phase as well as the toughness and plasticity of the metal matrix affect the breaking strength significantly.