N. Fatahalla et al., EFFECT OF THE PERCENTAGE CARBON EQUIVALENT ON THE NODULE CHARACTERISTICS, DENSITY AND MODULUS OF ELASTICITY OF DUCTILE CAST-IRON, Journal of Materials Science, 31(18), 1996, pp. 4933-4937
Successful melting and Mg treatment were conducted using a vortex unit
which produced spheroidal graphite (SG) Fe ingots having a percentage
carbon equivalent (%CE) ranging from 3.782 to 5.240. Microstructure e
xamination revealed graphite nodules embedded in a white matrix (unetc
hed condition). The variation of %CE proved to have a pronounced effec
t on the nodule characteristics. The nodule count showed a maximum val
ue at %CE of 4.613. For metal-mould ingots it reached a value of 1584
nodules mm(-2), while for sand-mould ingots it reached a value of 970
nodules mm(-2). Nodule size was found to be inversely proportional to
the nodule count for both sand- and metal-mould ingots. The nodularity
of all ingots was, in general, higher than 95%. The density of SG Fe
was found to decrease gradually (at %CE=3.782) from 7242 to 6969 kg m(
-3). The modulus of elasticity(E) showed a boat-like curve having mini
mum values of 189 and 192 GPa for the sa nd a nd metal moulds, respect
ively.