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Solutions for Fundamentals of Modern Manufacturing , 5e (published by Wiley)  MPGroover 2012

Answer. /he f!$tors in$lude (1) pourin" teper!ture !bove the eltin" point, (2) et!l !lloy $oposition, () vis$osity of the liuid et!l, !nd () he!t tr!nsfer to the surroundin"s.

10.12 10.12

Wh!t Wh!t does does he!t of fusion fusion e!n in $!stin $!stin"* "* Answer. 8e!t of fusion is the !ount of he!t ener"y reuired to tr!nsfor the et!l fro solid st!te to liuid st!te.

10.1

8o- does does solidifi$ solidifi$!tion !tion of of !lloys !lloys differ differ fro fro solidifi$!t solidifi$!tion ion of pure et!ls* et!ls* Answer. Pure et!ls solidify !t ! sin"le teper!ture eu!l to the eltin" point. Most !lloys (e&$eptions !re eute$ti$ !lloys) st!rt to solidify !t the liuidus !nd $oplete solidifi$!tion o$$urs !t the solidus, -here the liuidus is ! hi"her teper!ture th!n the solidus.

10.1 10.1

Wh!t Wh!t is ! eute eute$t $ti$ i$ !llo !lloy* y* Answer. % eute$ti$ !lloy is ! p!rti$ul!r $oposition in !n !lloy syste for -hi$h the solidus !nd liuidus teper!tures !re eu!l. /he teper!ture is $!lled the eute$ti$ teper!ture. 8en$e, solidifi$!tion o$$urs !t ! sin"le teper!ture, r!ther th!n over ! teper!ture r!n"e.

10.15

Wh!t is the the rel!tions rel!tionship hip 7no-n 7no-n !s 9hvorinov: 9hvorinov:ss rule rule in $!stin"* $!stin"*  ; C m(# < A)  A)2, -here " "S   ; tot!l solidifi$!tion tie, C m ; Answer. 9hvorinov:s rule is su!ried4 " "S  "S  ; "S  ; old $onst!nt, #  ;  ; volue of $!stin", !nd A !nd  A ;  ; surf!$e !re! of $!stin".

10.1

Identify Identify the the three three sour$es sour$es of of $ontr!$tion $ontr!$tion in ! et!l $!stin" $!stin" !fter !fter pourin". pourin". Answer. /he three $ontr!$tions o$$ur due to (1) $ontr!$tion of the olten et!l !fter pourin", (2) solidifi$!tion shrin7!"e durin" tr!nsfor!tion of st!te fro liuid to solid, !nd () ther!l $ontr!$tion in the solid st!te.

10.1 10.1

Wh!t Wh!t is ! $hi $hill ll in $!st $!stin in"* "* Answer. % $hill is ! he!t sin7 pl!$ed to en$our!"e r!pid freein" in $ert!in re"ions of the $!stin".

Probe!s %ns-ers to probles l!beled "A# !re listed in !n %ppendi& %ppendi& !t the b!$7 of the boo7. $e%tin& %n' Pourin&

10.1 "A# (SI units) % dis7 0 $ in di!eter !nd 5 $ thi$7 is $!st of pure !luinu in !n open old $!stin" oper!tion. %luinu elts !t 0 9, but the pourin" teper!ture -ill be 00 9. /he !ount of !luinu he!ted -ill be 5= ore th!n -h!t is needed to fill the old $!vity. 9opute the !ount of he!t th!t ust be !dded to the et!l to he!t it to the pourin" teper!ture, st!rtin" fro ! roo teper!ture of 25 9. /he he!t of fusion of !luinu ; 3. ><". ?ther properties $!n be obt!ined fro /!bles .1 !nd .2. %ssue the spe$ifi$ he!t h!s the s!e v!lue for solid !nd olten !luinu. Soution4 @olue #  ;  ;   $2h<; (0)2(5)< ; 2.2 $  @olue of !luinu to be he!ted ; 2.2(1 A 5=) ; 53. $  Bro /!ble .1 !nd .2, density    ;  ; 2.0 "<$  !nd spe$ifi$ he!t C  ;  ; 0.21 9!l<"# 9 ; 0. ><"# 9 8e!t reuired ; 2.0(53.)C0.(0#25) A 3. A 0.(00#0)D ; 1,12.1C55. A 3. A 12.2D ; 1()0*+),-. /

10.2 (ES9S units) units) Pure $opper $opper is he!ted he!ted to $!st ! l!r"e l!r"e re$t!n"ul! re$t!n"ul!rr pl!te in !n open open old. /he pl!teF pl!teFs len"th ; 20 in, -idth ; 10 in, !nd thi$7ness ; 2 in. 9opute the !ount of he!t th!t ust be !dded to the et!l to he!t it fro !bient teper!ture (5 B) to ! pourin" teper!ture of 2100 B. /he !ount of et!l he!ted -ill be 10= ore th!n -h!t is needed to fill the old $!vity. +ensity, eltin" point, !nd spe$ifi$ he!t of the solid et!l $!n be found in /!bles .1 !nd .2. /he spe$ifi$ he!t of $opper in the olten st!te ; 0.030 tu
10#2