Ductile cast iron subjected to austempering is shown to reach tensile strengths up to approx. 1600 N mm** minus **2 provided a strain of 1-2%. In the case of the tensile strength of 1000 N mm** minus **2, the strain is approx. 12-14%. The achievable strength and toughness properties are independent of the heat treatment. In addition to the good mechanical properties, the characteristic feature of this material group is high wear resistance.