  We present a comparison between simulation results and X-ray observational
data on the evolution of the metallicity of the intra-cluster medium (ICM). The
simulations of galaxy clusters were performed with the Tree-SPH Gadget2 code
that includes a detailed model of chemical evolution, by assuming three
different shapes for the stellar initial mass function (IMF), namely the
Salpeter (1955), Kroupa (2001) and Arimoto-Yoshii (1987) IMF. Our simulations
predict significant radial gradients of the Iron abundance, which extend over
the whole cluster virialized region. At larger radii, we do not detect any
flattening of the metallicity profiles. As for the evolution of the ICM metal
(Iron) abundance out to z=1, we find that it is determined by the combined
action of (i) the sinking of already enriched gas, (ii) the ongoing metal
production in galaxies and (iii) the locking of ICM metals in newborn stars. As
a result, rather than suppressing the metallicity evolution, stopping star
formation at z=1 has the effect of producing an even too fast evolution of the
emission-weighted ICM metallicity with too high values at low redshift.
Finally, we compare simulations with the observed rate of type-Ia supernovae
per unit B-band luminosity (SnU_B). We find that our simulated clusters do not
reproduce the decreasing trend of SnU_B at low redshift, unless star formation
is truncated at z=1.
