Page 261 - Manufacturing Engineering and Technology - Kalpakjian, Serope : Schmid, Steven R.

Liquid

L
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Q lLj_S_f°'oS___ ' S " ____
0
5 Q ' ' _
g Solid Q.
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P %
+
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\ Solid l<- Liquid
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Pure metal Alloying element (%) l\/lushy zone

Dendrites
-'i m
FIGURE I0.4 Schematic illustration of alloy solidification and temperature distribution in
the solidifying metal. Note the formation of dendrites in the mushy zone.

f’°”T‘**`¥*7§!>"”". 2%
' J
' »<e1 ;

"i§?¥%?\?§:'ef
8 11 40 60 90 102
Minutes after pouring
(H)
0.05-0.10% C 0.25-0.30% C 0.55-0.60% C
Steel Steel Steel
Sand Chill Sand Chill Sand Chill
mold mold mold mold mold mold
Q ' il il "H

-Tl ~ an
5 2 15 2 1 6 2
Minutes after pouring
(bl

FIGURE l0.5 (a) Solidification patterns for gray cast iron in a 180-mm square casting. Note
that after ll minutes of cooling, dendrites reach each other, but the casting is still mushy
throughout. It takes about 2 hours for this casting to solidify completely. (bl Solidification of
carbon steels in sand and chill (metal) molds. Note the difference in solidification patterns as
the carbon content increases. Source: After H.F. Bishop and WS. Pellini.

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