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J M a t e r S c i T e c h n 0 1 V 0 1 2 4N o 1 2 0 0 8 T h i n W a l lA l u m i n u mD i e C a s t i n gT e c h n o l o g yf o rD e v e l o p m e n t o fN o t e b o o kC o m p u t e rH o u s i n g C h a n g S e o g K a n g t J a e 一 kC h o C h a n g Y e o lJ e o n g S e W e o nC h o ia n dY o u n g C h a nI G m K o r e aI n s t i t u t eo fI n d u s t r i a lT e c h n o l o g y G w a n g j u K o r e a M a n u s c r i p tr e c e i v e dS e p t e m b e r3 2 0 0 7 6 5 S i l i c o n b a s e da l u m i n u mc a s t i n ga l l o y sa r ek n o w nt ob eo n eo ft h em o s tw i d e l yu s e da l l o ys y s t e m sm a i n l y d u et ot h e irs u p e r i o rc a s t l n gc h a r a c t e r i s t i c sa n du n i q u ec o m b i n a t i o no fm e c h a n i c a Ia n dp h y s i c a Ip r o p e r t i e s H o w e v e r m a n u f a c t u r i n go ft h i n w a l l e da l u m i n u md i e c a s t i n gc o m p o n e n t s I e s st h a nI 0m mi nt h i c k n e s s i s g e n e r a l l yk n o w nt ob ev e r yd i f f i c u l tt a s kt oa c h i e v ea I u m i n u mc a s t i n ga l l o y sw i t hh i g hf l u i d i t y T h e r e f o r e i n t h i ss t u d y t h eo p t i m a ld i e c a s t i n gc o n d i t i o n sf o rp r o d u c i n g2 9 7m mx2 1 0m mx0 7m mt h i n w a l l e da l u m i n u m c o m p o n e n tw a se x a m i n e de x p e r i m e n t a l l yb yu s i n g2d i f f e r e n tg a t i n gs y s t e m s t a n g e n t i a la n ds p l i tt y p e a n d v e n td e s i g n F ur t h e r m o r e c o m p u t a t i o n a ls o l i d i f i c a t i o ns i m u l a t i o nw a sa l s oc o n d u c t e d T h er e s u l t ss h o w e d t h a ts p l i tt y p eg a t i n gs y s t e mw a sp r e f e r a b l eg a t i n gd e s i g nt h a nt a n g e n t i a lt y p eg a t a n gs y s t e ma tt h ep o m t o fv i e wo fs o u n d n e s so fc a s t i n ga n dd i s t o r t i o ng e n e r a t e da f t e rs o l i d i f i c a t i o n I tw a sa l s of o u n dt h a tp r o p e r v e n td e s i g nw a so n eo ft h em o s ti m p o r t a n tf a c t o r sf o rp r o d u c i n gt h i n w a I c a s t i n gc o m p o n e n t sb e c a u s ei tw a s i m p o r t a n tf o rt h ef u l l m e n to ft h et h i n w a l lc a v i t ya n dt h em i n i m i z a t i o no ft h ec a s t i n gd i s t o r t i o n K E YW O R D S A l u m i n u m T h i n w a l ld i e c a s t i n g N o t e b o o kc o m p u t e rh o u s i n g C o l dc h a m b e r d i e c a s t i n gm a c h i n e 1 I n t r o d u c t i o n A m o n gt h ea l u m i n u mc a s t i n ga l l o y s t h eA 1 一S i b a s e da l l o ys y s t e m sa r eo n eo ft h em o s tw i d e l yu s e d a l l o ys y s t e m sb e c a u s eo ft h e i ru n i q u ec h a r a c t e r i s t i c s s u c ha s1 0 wd e n s i t y m o d e r a t e l y h i g hs t r e n g t h a n d g o o dc a s t a b i l i t y e t c 13 j R e c e n t l y t h ed e m a n df o r l i g h t w e i g h ta l l o y si 1 1 e l e c t r i c e l e c t r o n i ca n da u t o H I o b i l ec o m p o n e n th o u s i n g s u s i n ga l u m i n u mh a sb e e n g r e a t l yi n c r e a s e dm a i n l yb e c a u s ei ti sl i g h t w e i g h th a v i n gh i g hd a m p i n gc a p a c i t ya n dd e n tr e s i s t a n c ec o n l p a r e dt op l a s t i c s H o w e v e r i ti sg e n e r a l l yk n o w nt h a tm a n u f a c t u r i n go ft h i n w a l la l u m i n u mc o m p o n e n tw i t hat h i c k n e s sl e s st h a n1 0m m b yu s i n gh i g hp r e s s u r ed i ec a s t i n gp r o c e s si sq u i t ed i f f i c u l td u et oi t sl o wf l u i d i t y T h i sl e a d st ot h el i i n i t e da p p l i c a t i o no ft h ea l u m i n u m a l l o yi nt h e f i e l d so fh o u s i n go fe l e c t r i c e l e c t r o n i c c o m p o n e n t ss u c ha sn o t e b o o kc o m p u t e ra n dc e l l u l a r p h o n e e t c T h e r e f o r e i nt h i ss t u d y d i e c a s t i n gp r o c e s st e c h n o l o g yf o rt h ep r o d u c t i o no ft h i n w a l la l u m i n u mc o m p o n e n t sb a s e do nt h ei n v e s t i g a t i o no ft h e o p t i m a ld i ed e s i g ni n c l u d i n gr u n n e r sa n dg a t i n gs y s t e ma n dc a s t i n gc o n d i t i o n sw a si n v e s t i g a t e d M o r e o v e r e x p e r i m e n t a le x a m i n a t i o n so fg a t i n gd e s i g ne l f e c t so nt h ef a b r i c a t i o np r o c e s s i n go fs o u n dt h i n w a l l a l u m i n u mn o t e b o o kh o u s i n gw i t hat h i c k n e s so fl e s s t h a n0 8n l n l 2 E x p e r i m e n t a l P r i o rt ot h ea c t u a ld i e c a s t i n ge x p e r i m e n t c a s t i n g s i m u l a t i o nv c a sc o n d u c t e dt os e tu pt h ed i e c a s t i n g a n dm e l tc o n d i t i o n s D i e c a s t i n gd i em a d eo u to f H 1 3t o o ls t e e lf o rt h et h i n w a l ln o t e b o o kh o u s i n gi n s i z eo f2 1 0H i m x 2 9 7n l n l 0 7i n n lw a sd e s i g n e da n d f a b r i c a t e df o rt h ee x p e r i m e n t A ss h o w ni n F i g 1 十 P h D t ow h o mc or 1 1 e 8 p o n d e n c es h o u l db ea d d r e s s e d E m a i hc s k a n 9 7 k i t e c h r e k r t h e2d i f f e r e n tt y p e so fg a t i n gs y s t e m t a n g e n t i a lt y p e a n ds p l i tt y p e w e r eu s e df o rt h i si n v e s t i g a t i o n Ac o m m e r c i a lA L D C l 2a l u m i n u md i e c a s t i n g a l l o y A 1 一 9 6 1 2 s i 一 1 53 5 C u T a b l e1 w a s m e l t e du pt o7 8 0 Ca n dt h ed i ew a sh e a t e du pt o 2 3 0 Cb e f o r et h ed i ec a s t i n g T h em a j o rs p e c i f i c a t i o n so ft h ec o l dc h a m b e rd i e c a s t i n gm a c h i n ef F i g 2 u s e df o rt h i ss t u d ya r es h o w ni nT a b l e2 M o l t e na l u m i n u ma l l o yw a si n j e c t e di n t ot h ed i ec a v i t yu n d e r t h ec o n d i t i o n so f0 3 5m si ni n j e c t i o ns p e e du n t i lt h e p l u n g e rt r a v e l e du pt o3 7 0H i mi ns h o ts l e e v ea n d t h e nt h ei n1 iection s p e e dw a sa c c e l e r a t e di n e a r l yt o t h eh i g hi n j e c t i o ns p e e do f2 0 2 5 3 0 3 5 4 0a n d 4 5m sf r o n l3 7 0i n mt o3 9 0H i mi ns h o ts l e e v e T a b l e3s h o w st h es u m m a r yo fd i e c a s t i n gc o n d i t i o n sf o r t h i si n v e s t i g a t i o n 3 R e s u l t sa n dD i s c u s s i o n T h es o l i d i 蠡c a t i o ns i m u l a t i o nw a sc o n d u c t e df o r2 d i f f e r e n tg a t ed e s i g n s t a n g e n t i a la n ds p l i tt y p ep r i o r t ot h ed i e c a s t i n ge x p e r i m e n t T h ef l o wp a t t e r na n d t e m p e r a t u r ed i s t r i b u t i o nd u r i n gf i l l i n go fa l u m i n u m m e l tw i t ht h eg a t ed e s i g n ss t u d i e da r es h o w ni nF i g 3 I tw a sf o u n dt h a tb o t hg a t ed e s i g n se x h i b i t e dq u i t e u n i f o r mm e l tf l o wt h r o u g h o u tt h ef i l l i n go ft h ec a v i t y H o w e v e r t h et a n g e n t i a lt y p eg a t ed e s i g n r e s u i t e di nt h em e l tt e m p e r a t u r ed r o p p e da r e afc i r c l e d i i lF i g 3 a a tt h el a s ts t a g eo ff i l l i n gw h i l et i l es p l i t t y p eg a t ed e s i g na l l o w e dt h em e l tt of i l lt h ec a v i t y a b o v et h el i q u i d u st e m p e r a t u r e A sm e n t i o n e d a c t u a ld i e c a s t i n ge x p e r i m e n t sw e r e c o n d u c t e df o rt h en o t e b o o kc o m p u t e rh o u s i n gi ns i z e o f2 1 0m i D 2 9 7n l n l X 0 7t o n i F i g u r e4s h o w st h er e s u l t a n tc a s t i n g sw i t hv a r i e dh i g hs p e e di n j e c t i o nf r o m 2 0t o4 5m sw h i l e1 0 ws p e e di n j e c t i o nw a sf i x e dt o 0 3 5m s A ss h o w n b o t hg a t ed e s i g n sa l l o w e df i l l i n g t h ec a s t i n gw i t hh i g hs p e e di n j e c t i o no fm o r et h a n 3 0m s H o w e v e r l e s st h a n3 0m so fh i g hs p e e d i n j e c t i o nf a i l e dt of i l l t h et h i n w a l lc a v i t y I tw a s 万方数据 6 6J M a t e r S c i T e c h n 0 1 V 0 1 2 4N o 1 2 0 0 8 T a b l e1C h e m i c a lc o m p o s i t i o n so fA L D C l 2a l l o y i nw tp c t T a b l e2S p e c i f i c a t i o no fd i e c a s t i n gm a c h i n e 5 2 5 04 9 0 砂7 0 T a b l e3D i e c a s t i n ge x p e r i m e n tc o n d i t i o n s 7 8 02 3 0 2 0 2 5 3 0 3 5 4 0 4 5 0 3 5 F i g 1 S c h e m a t i ci l l u s t r a t i o nn o t e b o o kh o u s i n g 2 1 0m m x 2 9 7I l l I l l X o 8n l m a n d2d i f f e r e n tg a t ed e s i g n s a t a n g e n t i a lt y p e b s p l i tt y p e F i g 2H i g hs p e e dd i e c a s t i n gm a c h i n e 万方数据 E E C Q 芑 凸 J M a t e r S c i T e c h n 0 1 V 0 1 2 4N o 1 2 0 0 8 F i g 3S i m u l a t i o nr e s u l t so f2d i f f e r e n tg a t ed e s i g n s a t a n g e n t i a lt y p e b s p l i tt y p e F i g 4D i e c a s t i n gr e s u l t sb yv a r y i n gt h eh i g hs p e e di n j e c t i o n a t a n g e n t i a lt y p e b s p l i tt y p e D i s t a n c e m m F i g 5D i s t o r t i o no ft a n g e n t i a la n ds p l i tt y p eg a t i n gs y s t e ma f t e rt h er e m o v a lo fg a t e s a l s of o u n dt h a tt h et a n g e n t i a lt y p eg a t ed e s i g nw a s n o ta b l et o6 1 lt h eo v e r f l o we v e na tt h eh i g h e s ti n j e c t i o ns p e e du s e df o rt h i si n v e s t i g a t i o n M o r e o v e r t h e t a n g e n t i a lt y p eg a t i n gs y s t e mr e s u l t e di nm o r ed i s t o r t i o no ft h ec a s t i n ga f t e rt h er e m o v a lo ft h eg a t e 6 7 I nF i g 5 t h ea m o u n to fd i s t o r t i o nm e a s u r e da f t e r r e m o v a lo fe a c hg a t i n gs y s t e mw a sd i s p l a y e d T h e r e s u l tc l e a r l ys h o w e dt h a tt h et a n g e n t i a lt y p eg a t i n gs y s t e mc o u l dr e s u l t e di nm o r es e v e r ed i s t o r t i o n t h a ns p l i tt y p e S i n c en o t e b o o kh o u s i n gf a b r i c a t e di n t h i sr e s e a r c hw a so n l y0 7m mi nt h i c k n e s s t h es t r e s s b u i l du pb e c a u s eo ft h es h r i n k a g eo fc a s t i n ga f t e rt h e c o m p l e t i o no fs o l i d i f i c a t i o nw a sa ni m p o r t a n tf a c t o r t oc o n s i d e rf o rt h em a s sp r o d u c t i o no ft h en o t e b o o k h o u s i n g T h e r e f o r e i tw a sc o n c l u d e dt h a tt h es p l i t t y p eg a t ed e s i g nw a sb e t t e rt h a nt h et a n g e n t i a lt y p e b e c a u s eo ft h ea f o r e m e n t i o n e dm a t t e r s H o w e v e r e v e nw i t hs p l i tt y p eg a t ed e s i g nt h e r e w e r ec a s t i n gd e f e c t ss u c ha sf l o wl i n ea n dm i s r u nd u r i n gd i e c a s t i n g T h e r e f o r e t w om a j o rm o d i f i c a t i o n s w e r ei n t r o d u c e d O n ew a st h ei n c r e a s eo ft h eo v e r f l o wa n dv e n ts i z e s T h ev o l u m eo ft h eo v e r f l o ww a s i n c r e a s e da b o u t7 0 f f r o m4 4 0 0m m 3t o7 5 0 0m m 3 a n dt h eo v e r f l o wi n g a t e l e n g t hw a sa l s oi n c r e a s e df r O l n 1 3 5m mt o3 0m mi nt o t a ll e n g t hf o rt h eb e t t e rf l o w o fa i ri nt h ed i ec a v i t y M o r e o v e r u p p e rp a r to fs l e e v e w a sm a c h i n e dt oh a v ei n c l i n e ds l o p ea ss h o w ni nF i g 6 万方数据 6 8 J M a t e r S c i T e c h n 0 1 V 0 1 2 4N o 1 2 0 0 8 F i g 6S c h e m a t i ci l l u s t r a t i o no ft h ei n c l i n e ds l o p es l e e v e F i g 7 T h i n w a l ln o t e b o o kh o u s i n gw i t hat h i c k n e s so fO 7m i l l G a t es y s t e m L o c a t i o n F i g 8T h et h i c k n e s so ft h i n w a l ln o t e b o o kh o u s i n g t om i n i m i z et h et u r b u l e n c ea n da i re n t r a p m e n ti n s i d e o ft h es l e e v ed u r i n gi n iection B e c a u s et h es l e e v eW a S f i l l e dw i t ha l u m i n u ml e s st h a n3 0 f m i n i m u mo f4 0 o f s l e e v ef i l l i n gi sr e c o m m e n d e di n d i e c a s t i n gp r o c e s si n f i e l d lr e s u l t i n gl a r g ea m o u n to fe n t r a p p e da i r a n dh i g ht u r b u l e n c ed u r i n gi n j e c t i o nL 4 J A st h eF i g 6 s h o w s t h em a c h i n e ds l o p ew o u l dh e l pa i ri n s i d eo ft h e s l e e v et of l o wo u tm o r ee a s i l yd u r i n gi n t h a 土 i e c t i o nS O t h ea i re n t r a p m e n ti nt h em e l tw o u l db em i n i m i z e d W i t h t w om o d i f i c a t i o n sm e n t i o n e de a r l i e r s o u n dt h i n w a l ln o t e b o o kh o u s i n gc a s t i n gw i t hl e s sd e f e c tW a S s u c c e s s f i f l l yf a b r i c a t e d F i g 7 1 T h e r ef o u n dt ob el e s s f l o wl i n e c r a c ka n dm i s r u nd e f e c t si nt h ec a s t i n g T h e t h i c k n e s so ft h ec a s t i n gw a sm e a s u r e df F i g 8 1 I nl e f t f i g u r e t h el o c a t i o n so ft h et h i c k n e s sm e a s u r e da n da r e s h o w na n dt h er i g h tf i g u r es h o w st h en l e a s u r e dt h i c k EE o亡芏 I u I 万方数据 J M a t e r S c i T e c h n 0 1 V 0 1 2 4N o 1 2 0 0 8 n e s so ft h ec a s t i n g T h et h i c k n e s sw a sf o u n dt ob e q u i t eu n i f o r ma n da v e r a g et h i c k n e s so f0 6 7n l n lw a s o b t a i n e d B e c a u s et h ec a s t i n gw a ss ot h i n l e s st h a n0 7i n n l t h ee 一 i e c t i o nf r o n l t h e d i e a f t e r l t h es o l i d i f i c a t i o n becanle v e r yi m p o r t a n tT b i nw a lc a s t i n gc o u l db eb e n t o re v e nc r a c k e dd u r i n gt h ee j e c t i o n t h e r e f o r e t h e n u m b e ro fe j e c t o rp i na n di t s1 a yo u tw e r ev e r yc r i t i c a l i nd i ed e s i g n M o r e o v e r t h eu s eo fd i et e m p e r a t u r e c o n t r o l l e rW a Sa l s oa ni m p o r t a n tf a c t o rf o rf u l f i l l m e n t o fd i ec a v i t yf o rt h i n w a l ld i e c a s t i n g I tw a sf o I u n d t h a tw i t h o u tt h ed i et e m p e r a t u r ec o n t r o l l e r t h ed i e W a Sn o th e a t e du pS O f f i c i e n t l ye v e nw i t hm o r et h a n 2 0t i m e so fi n j e c t i o n W h e nt h ed i ed i dn o tb eh e a t e d u pt oa p p r o p r i a t et e m p e r a t u r e t h em e l tw o u l db e r a p i d l yc o o l e dd o w nw h e ni ti n j e c t e di n s i d eo ft h e c o l dd i ec a v i t y A sar e s u l t s e v e r ec a s t i n gd e f e c t si n e l u d i n gm i s r u na n dc r a c k sw e r ee x h i b i t e dw i t h o u td i e t e m p e r a t u r ec o n t r 0 1 4 C o n c l u s i o n 1 B e t w e e nt a n g e n t i a la n ds p l i t t y p eg a t ed e s i g n s s p l i tt y p eg a t i n gs y s t e mW a Sf o u n dt ob eb e t t e rf o r t h i n w a l ld i e c a s t i n gb e c a u s et h em e l tf l o w sm o r eu n i f o r m l yi n s i d et h ed i ec a v i t y 2 A st h em e l tr e a c h e dt h ei n g a t e t h eh i g hs p e e d i n j e c t i o nn e e d e dt ob eh i g h e rt h a n3 0m S p r e f e r a b l y4 5m s f o rs o u n dt h i n w a l ld i e c a s t i n gi ns i z eo f 6 9 n o t e b o o kc o m p u t e rh o u s i n g 3 T h et h i c k n e s s w a su n i f o r mt h r o u g h o u tt h e c a s t i n ga n da v e r a g et h i c k n e s s o f0 6 7n U l lw a so b t a i n e d 4 F o rt h i n w a l la l u m i n u md i e c a s t i n g t h el o c a t i o na n dt h es i z eo fa i rv e n ta n do v e r f l o ww e r ei m p o r t a n tf a c t o r sf o rm i n i m i z i n gt h ef l o wl i n ea n di n i s r u n d e f e c t si nt h ec a s t i n g 5 I n c l i n e ds l o p es l e e v ed e s i g nW a Sh e l p f u lf o ra i r e n t r a p p e di n s i d eo f s l e e v et of l o wo u td u r i n gi n j e c t i o n 6 B e c a u s et h ec a s t i n gv o l u m eW a Sq u i t es m a l l i t i si m p o r t a n tt oC O n t r o lt h ed i et e m p e r a t u r e3 8h i g h3 8 p o s s i b l e A c k n o w l e d g e m e n t T h i sw o r kw a ss u p p o r t e db yK o r e aI n s t i t u t eo fI n d u s t r i a lT e c h n o l o g ya n dC w a n g j uM e t r o p o l i t a nC i t yt h r o u g h T h eA d v a n c e dM a t e r i a l sa n dC o m p o n e n t sI n d u s t r yD e v e l o p m e n tP r o g r a m 2 3 4 R E F E R E N C E S M i c r o s t r u c t u r ea n dP r o p e r t i e so fA l u m i n u mA l l q y s T h eJ a p a nI n s t o fL i g h tM e t a l s 1 9 9 1 2 3 3 G K S i g w o r t h A F ST r a I I S 1 9 8 3 9 1 7 J E G r u z l e s k ia n dB e r n a r dM C l o s s e t A F S 1 9 9 0 1 3 W G h l k i n g t o n D i eC a s t i n gD e f e c t s N A D C A 1 9 9 7 万方数据 Thin Wall Aluminum Die Casting Technology forThin Wall Aluminum Die Casting Technology for Development of Notebook Computer HousingDevelopment of Notebook Computer Housing 作者 Chang Seog Kang Jae Ik Cho Chang Yeol Jeong Se Weon Choi Young Chan Kim 作者单位 Korea Institute of Industrial Technology Gwangju Korea 刊名 材料科学技术学报 英文版 英文刊名 JOURNAL OF MATERIALS SCIENCE TECHNOLOGY 年 卷 期 2008 24 1 引用次数 0次 参考文献 4条 参考文献 4条 1 Microstructure and Properties of Aluminum Alloys 1991 2 G K Sigworth 查看详情 1983 3 J E Gruzleski Bernard M Closset 查看详情 1990 4 W G Walkington Die Casting Defects 1997 相似文献 3条 相似文献 3条 1 期刊论文 Young Chan Kim Chang Seog Kang Jae Ik Cho Chang Yeol Jeong Se Weon Choi Sung Kil Hong Die Casting Mold Design of the Thin walled Aluminum Case by Computational Solidification Simulation 材料科学技术学报 英文版 2008 24 3 Recently demand for the lightweight alloy in electric electronic housings has been greatly increased However among the lightweight alloys aluminum alloy thin walled die casting is problematic because it is quite difficult to achieve sufficient fluidity and feedability to fill the thin cavity as the wall thickness becomes less than 1 mm Therefore in this study thin walled die casting of aluminum Al Si Cu alloy ALDC 12 in size of notebook computer housing and thickness of 0 8 mm was investigated by solidification simulation MAGMA soft and actual casting experiment Buhler Evolution B 53D Three different types of gating design finger tangential and split type with 6 vertical runners were simulated and the results showed that sound thin walled die casting was possible with tangential and split type gating design because those gates allowed aluminum melt to flow into the thin cavity uniformly and split type gating system was preferable gating design comparing to tangential type gating system at the point of view of soundness of casting and distortion generated after solidification Also the solidifi
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