46:
According to the rule, a casting with a larger surface area and smaller volume will cool more quickly than a casting with a smaller surface area and a larger volume under otherwise comparable conditions. The relationship can be mathematically expressed as:
99:
454:
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will solidify before the casting, because if the riser solidifies first then defects like shrinkage or porosity can form.
53:
677:
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241:
266:
615:"Statistical Investigation of the Effects of Shape, Size and Superheat on Solidification Times of Castings"
183:
594:(1940). "Theorie der Erstarrung von Gussstücken" [Theory of the Solidification of Castings].
699:
693:"Casting Analysis - 2. Solidification and cooling. Surface tension. Gas solubility and porosity"
137:
229:
8:
735:
673:
614:
117:
38:
of the casting. It was first expressed by Czech engineer
Nicolas Chvorinov in 1940.
571:
256:
is usually 2, however
Degarmo claims it is between 1.5 and 2. The mold constant
225:
23:
724:
221:
35:
652:
Fundamentals of Modern
Manufacturing: Materials, Processes, and Systems
228:
and superheat, and the mold, such as initial temperature, density,
27:
472:
31:
668:
Degarmo, E. Paul; Black, J. T.; Kohser, Ronald A. (2003),
612:
177:
is the ratio of the casting's volume to its surface area:
220:
depends on the properties of the metal, such as density,
654:. Hoboken, NJ: John Wiley & Sons, Inc. p. 223.
269:
186:
140:
116:
is the surface area of the casting that contacts the
56:
471:= melting or freezing temperature of the liquid (in
131:This relationship can be expressed more simply as:
667:
613:Tiryakioglu, M.; Tiryakioglu, E.; Askeland, D. R.
448:
205:
162:
94:{\displaystyle t=B\left({\frac {V}{A}}\right)^{n}}
93:
698:. Georgia Institute of Technology. Archived from
722:
637:Essentials of Materials Science and Engineering
635:Askeland, Donald R.; Phule, Pradeep P. (2004),
486:= initial temperature of the mold (in kelvins),
260:can be calculated using the following formula:
634:
22:is a physical relationship that relates the
630:
628:
663:
661:
590:
528:= thermal conductivity of the mold (in ),
670:Materials and Processes in Manufacturing
649:
625:
252:). According to Askeland, the constant
723:
658:
570:It is most useful in determining if a
449:{\displaystyle B=\left^{2}\left\left,}
232:, heat capacity and wall thickness.
672:(9th ed.), Wiley, p. 282,
602:(10–12): 177–186, 201–208, 222–225.
566:= specific heat of the metal (in ).
13:
544:= specific heat of the mold (in ),
416:
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14:
747:
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206:{\displaystyle M={\frac {V}{A}}}
685:
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520:= latent heat of fusion (in ),
248:is seconds per metre squared (
112:is the volume of the casting,
41:
1:
577:
555:= density of the metal (in ),
536:= density of the mold (in ),
108:is the solidification time,
7:
650:Groover, Mikell P. (2010).
10:
752:
639:, Ontario, Canada: Thomson
16:Concept in applied physics
512:= superheat (in kelvins),
163:{\displaystyle t=BM^{n}}
731:Casting (manufacturing)
128:is the mold constant.
450:
244:for the mold constant
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230:thermal conductivity
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124:is a constant, and
705:on 14 January 2015
592:Chvorinov, Nicolas
446:
216:The mold constant
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173:Where the modulus
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26:time for a simple
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20:Chvorinov's rule
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226:heat of fusion
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24:solidification
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679:0-471-65653-4
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598:(in German).
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236:Mold Constant
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222:heat capacity
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707:. Retrieved
700:the original
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103:
45:
36:surface area
19:
18:
42:Description
736:Metallurgy
725:Categories
709:14 January
621:: 907–913.
578:References
596:Giesserei
408:Δ
364:ρ
354:π
318:−
286:ρ
242:S.I. unit
504:−
473:kelvins
30:to the
28:casting
676:
549:ρ
533:ρ
490:Δ
459:Where
104:Where
32:volume
703:(PDF)
696:(PDF)
572:riser
711:2015
674:ISBN
502:pour
240:The
118:mold
34:and
250:s/m
727::
660:^
627:^
617:.
600:27
497:=
475:),
224:,
120:,
713:.
563:m
560:c
552:m
541:c
525:k
517:L
509:m
506:T
499:T
495:s
492:T
483:0
480:T
468:m
465:T
444:,
440:]
434:2
429:)
424:L
417:s
412:T
402:m
397:c
390:(
385:+
382:1
378:[
373:]
367:c
361:k
358:4
349:[
343:2
338:]
332:)
326:0
322:T
312:m
307:T
302:(
297:L
291:m
279:[
274:=
271:B
258:B
254:n
246:B
218:B
199:A
196:V
191:=
188:M
175:M
156:n
152:M
148:B
145:=
142:t
126:B
122:n
114:A
110:V
106:t
87:n
82:)
77:A
74:V
69:(
64:B
61:=
58:t
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.