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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 n1iection 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 actua

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