The paper presents the results of the research on the effect of copper on the crystallization process, microstructure and selected properties
of the compacted graphite iron. Compacted graphite in cast iron was obtained using Inmold process. The study involved the cast iron
containing copper at a concentration up to approximately 4%. The effect of copper on the temperature of the eutectic crystallization as well
as the temperature of start and finish of the austenite transformation was given. It has been shown that copper increases the maximum
temperature of the eutectic transformation approximately by 5C per 1% Cu, and the temperature of the this transformation finish
approximately by 8C per 1% Cu. This element decreases the temperature of the austenite transformation start approximately by 5C per
1% Cu, and the finish of this transformation approximately by 6C per 1% Cu. It was found that in the microstructure of the compacted
graphite iron containing about 3.8% Cu, there are still ferrite precipitations near the compacted graphite. The effect of copper on the
hardness of cast iron and the pearlite microhardness was given. This stems from the high propensity to direct ferritization of this type of
cast iron. It has been shown copper increases the hardness of compacted graphite iron both due to its pearlite forming action as well as
because of the increase in the pearlite microhardness (up to approx. 3% Cu). The conducted studies have shown copper increases the
hardness of the compacted graphite iron approximately by 35 HB per 1% Cu.