The work determined the influence of aluminium in the amount from about 0.6% to about 8% on graphitization of cast iron with

relatively high silicon content (3.4%-3.9%) and low manganese content (about 0.1%). The cast iron was spheroidized with cerium mixture

and graphitized with ferrosilicon. It was found that the degree of graphitization increases with an increase in aluminium content in cast

iron up to 2.8%, then decreases. Nodular and vermicular graphite precipitates were found after the applied treatment in cast iron containing

aluminium in the amount from about 1.9% to about 8%. The Fe3AlCx carbides, increasing brittleness and deteriorating the machinability of

cast iron, were not found in cast iron containing up to about 6.8% Al. These carbides were revealed only in cast iron containing about 8% Al.