ABSTRACTThe chill depth and mechanical properties of gray iron
affected by metallurgical parameters were fully investigated in
this study. The chill specimens were prepared from pouring
molten gray iron into a wedge type of shell core sand.
Specimens for measuring mechanical properties were taken from Y-
block castings. The different amounts of inoculants and their
compositions, carbon equivalent, taping temperature, different
molding sands, holding time, and inoculation method affected
the microstructures of gray irons resulted in varying chill
depths and mechanical properties.Experimental results showed
that a 5% of inoculant addition could fully depress the
formation of chill. At taping temperature of 1410-1510℃
associated with carbon equivalent 4.4%(C:3.6%, Si:1.8%)
resulted in nil chill depth. Inoculants added with Al, Ca, and
Bi composition played an important role to reduce chill value.
If iron (C.E=3.8-4.2%) treated with longer holding time and
poured at higher temperature, serious fading would occur and
resulted in a great chill value. In addition, mechanical
properties of gray irons were dominated by carbon equivalent,
fading time, as well as moisture of green sand. Post-post
inoculation could signification improve the mechanical
properties and reduced the chill values of gray irons.
Keywords: gray iron, inoculant, inoculation, chill depth, carbon
equivalent