In the paper, a relationship between chemical composition of Ni-Mn-Cu cast iron and its structure, hardness and corrosion resistance is
determined. The examinations showed a decrease of thermodynamic stability of austenite together with decreasing nickel equivalent value,
in cast iron solidifying according to both the stable and the metastable systems. As a result of increasing degree of austenite
transformation, the created martensite caused a significant hardness increase, accompanied by small decline of corrosion resistance. It was
found at the same time that solidification way of the alloy and its matrix structure affect corrosion resista
Within the presented work, the effect of austenite transformation on abrasive wear as well as on rate and nature of corrosive destruction
of spheroidal Ni-Mn-Cu cast iron was determined. Cast iron contained: 3.1÷3.4 %C, 2.1÷2.3 %Si, 2.3÷3.3 %Mn, 2.3÷2.5 %Cu and
4.8÷9.3 %Ni. At a higher degree of austenite transformation in the alloys with nickel equivalent below 16.0%, abrasive wear resistance
was significantly higher. Examinations of the corrosion resistance were carried out with the use of gravimetric and potentiodynamic
method. It was shown that higher degree of austenite transformation results in significantly higher abrasive wear resistance and slightly
higher corrosion rate, as determined by the gravimetric method. However, results of potentiodynamic examinations showed creation
of a smaller number of deep pinholes, which is a favourable phenomenon from the viewpoint of corrosion resistance.