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Application of shear controlled orientation technology to powder injection moulding
PM
FABRICATION OF ALUMINA R E I N F O R C E D NICKEL ALUMINIDE COMPOSITES
Fenzo et al, (Himeji Inst of Technology, Himeji, J a p a n ) , J Japan Soc Powder and PowderMetaUurgy, Vo! 39, No 6, 1992, 474478. (In J a p a n e s e ) . Ni-Mo-TiC samples were p r e p a r e d from p o w d e r a n d v a c u u m h o t p r e s s e d . The s p e c i m e n s were h e a t e d to m e l t i n g in microgravity conditions. The s t r u c t u r e s are shown to consist of globular TiC particles in a Ni-Mo m a t r i x a n d the d i s t r i b u t i o n s of e l e m e n t s w e r e d e t e r m i n e d by A u g e r spectroscopy. It is suggested t h a t t h e r m a l convection a n d gravity segregation were a b s e n t a s a r e s u l t of m i c r o g r a v i t y processing.
Mechanical alloying MECHANICAL ALLOYING IN THE IRONCOPPER SYSTEM
K. Uenishi et al, (Osaka University, Osaka, J a p a n ) , Z fiir Metallkunde, Vol 83, No 2, 1992, 132-135. It is shown t h a t t h e MA of Fe-Cu alloy powder m i x t u r e s p r o d u c e s s u p e r s a t u r a t e d solid solutions of 30 at% Cu in body centred cubic Fe a n d 40% in face centred cubic Fe. The solubilities exceed t h o s e f o u n d in liquid or v a p o u r q u e n c h e d alloys. PREPARATION OF AMORPHOUS NICKEL-MOLYBDENUM ALLOY POWDERS BY MECHANICAL ALLOYING
M.V. Zdujic et al, (Serbian Academy of Sciences a n d Arts, Belgrade, Ygoslavia), Z fu'r Metallkunde, Vol 83, No 2, 1992, 136139. The p r o d u c t i o n of a m o r p h o u s Ni-50 at% Mo powders by MA of e l e m e n t a l powders in a conventional ball mill is reported. The a m o r p h o u s n a t u r e a n d t h e r m a l stability of t h e milled powders were d e t e r m i n e d as a function of milling time.
LITERATURE
REVIEW
Metal injection moulding APPLICATION OF SHEAR CONTROLLED ORIENTATION TECHNOLOGY TO POWDER I N J E C T I O N MOULDING
MJ. Bevis et al, (Brunel University, Uxbridge, UK), Powder Metallurgy, Vol 35, No 2, 1992, 107-112. T h e t e c h n i q u e of SCORIM ( s h e a r c o n t r o l l e d o r i e n t a t i o n t e c h n o l o g y in injection moulding) h a s been applied a n d it is shown t h a t p a r t s w i t h a reduced i n c i d e n c e of d e f e c t s a n d c l o s e r t o d i m e n s i o n a l tolerances, can be produced. There is also t h e ability to p r o d u c e p a r t s with aligned fibre reinforcements. SCORIM is carried out on a twin screw injection moulding m a c h i n e w h i c h allows oscillation of t h e hold p r e s s u r e a n d b l e n d i n g / m i x i n g of t h e raw materials. The process a n d its a d v a n t a g e s are discussed. SHRINKAGE D U R I N G REMOVAL OF ORGANIC VEHICLE FROM INJECTION MOULDED ALUMINUM B O D I E S
MJ. Bevis et al, (Brunel University, Uxbridge, UK), Powder Metallurgy, Vol 35, No 2, 1992, 113-116. The use of a polypropylene vehicle for i n j e c t i o n m o u l d i n g of A1 p o w d e r is described. Shrinkage a n d s t r e n g t h of t h e t e s t p a r t s were m e a s u r e d a t i n t e r v a l s d u r i n g t h e d e b i n d i n g operation. As t h e b i n d e r w a s r e m o v e d t h e vol% of A1 increased a n d increases in s t r e n g t h are reported. It is n o t e d t h a t t h e p a c k i n g efficiency is below t h e m a x i m u m value.
PM parts PRODUCTION OF CAMS BY POWDER METALLURGY
Erlagen-Nuremburg,
Erlagen,
Germany),
Powder Metall Int Vol 24, No 5, 1992, 284288. The p r o d u c t i o n of cams from powder is described. Problems arising in p r o d u c t i o n a n d use are discussed. The i m p o r t a n c e of minimizing cost by avoiding t h e use of expensive alloying e l e m e n t s is emphasized. Wear resistance under lubricated conditions ( n o r m a l ) a n d emergency (unlubricated) conditions are taken into account. NEW SYSTEM FOR THE PRODUCTION OF HELICAL GEAR COMPONENTS
H. Good, (Werkzeugbau Alvier AG, Buchs, Switzerland), Powder Metall Int, Vol 24, No 5, 1992, 305. The p r o d u c t i o n of helical gears by a new m e t h o d is described. Modular tooling of t h e p r o c e s s is c o n s i d e r e d . T h e t e c h n i q u e involves r o t a t i o n of t h e tooling to allow s h a p i n g of t h e gear t o o t h profile a n d final sizing.
Miscellaneous S T R U C T U R E S AND MECHANICAL P R O P E R T I E S OF AMORPHOUS ALLOY COMPACTS MADE IN AN INERT ATMOSPHERE
Y. K a w a m u r a et al, (Tohoku University, Sendal, J a p a n ) , J Materials Science, Vol 27, No 4, 1992, 956-962. The use of a n Ar a t m o s p h e r e to reduce oxidation of a n alloy a t all process stages is discussed. The powder was p r o d u c e d by f r a g m e n t a t i o n of a m o r p h o u s r i b b o n s in a p l a n e t a r y ball mill a n d consolidation was by m e a n s of a cubic anvil a p p a r a t u s at high pressures. I t is r e p o r t e d that the c o m p r e s s i v e s t r e n g t h of t h e alloy was increased by 30 to 100% c o m p a r e d with materials p r e p a r e d in air. The alloy used is described as Metglas 2605-2.
F. Vollertsen a n d U. Engel, (University of
MPR March 1993 55
FABRICATION OF ALUMINA R E I N F O R C E D NICKEL ALUMINIDE COMPOSITES
Fenzo et al, (Himeji Inst of Technology, Himeji, J a p a n ) , J Japan Soc Powder and PowderMetaUurgy, Vo! 39, No 6, 1992, 474478. (In J a p a n e s e ) . Ni-Mo-TiC samples were p r e p a r e d from p o w d e r a n d v a c u u m h o t p r e s s e d . The s p e c i m e n s were h e a t e d to m e l t i n g in microgravity conditions. The s t r u c t u r e s are shown to consist of globular TiC particles in a Ni-Mo m a t r i x a n d the d i s t r i b u t i o n s of e l e m e n t s w e r e d e t e r m i n e d by A u g e r spectroscopy. It is suggested t h a t t h e r m a l convection a n d gravity segregation were a b s e n t a s a r e s u l t of m i c r o g r a v i t y processing.
Mechanical alloying MECHANICAL ALLOYING IN THE IRONCOPPER SYSTEM
K. Uenishi et al, (Osaka University, Osaka, J a p a n ) , Z fiir Metallkunde, Vol 83, No 2, 1992, 132-135. It is shown t h a t t h e MA of Fe-Cu alloy powder m i x t u r e s p r o d u c e s s u p e r s a t u r a t e d solid solutions of 30 at% Cu in body centred cubic Fe a n d 40% in face centred cubic Fe. The solubilities exceed t h o s e f o u n d in liquid or v a p o u r q u e n c h e d alloys. PREPARATION OF AMORPHOUS NICKEL-MOLYBDENUM ALLOY POWDERS BY MECHANICAL ALLOYING
M.V. Zdujic et al, (Serbian Academy of Sciences a n d Arts, Belgrade, Ygoslavia), Z fu'r Metallkunde, Vol 83, No 2, 1992, 136139. The p r o d u c t i o n of a m o r p h o u s Ni-50 at% Mo powders by MA of e l e m e n t a l powders in a conventional ball mill is reported. The a m o r p h o u s n a t u r e a n d t h e r m a l stability of t h e milled powders were d e t e r m i n e d as a function of milling time.
LITERATURE
REVIEW
Metal injection moulding APPLICATION OF SHEAR CONTROLLED ORIENTATION TECHNOLOGY TO POWDER I N J E C T I O N MOULDING
MJ. Bevis et al, (Brunel University, Uxbridge, UK), Powder Metallurgy, Vol 35, No 2, 1992, 107-112. T h e t e c h n i q u e of SCORIM ( s h e a r c o n t r o l l e d o r i e n t a t i o n t e c h n o l o g y in injection moulding) h a s been applied a n d it is shown t h a t p a r t s w i t h a reduced i n c i d e n c e of d e f e c t s a n d c l o s e r t o d i m e n s i o n a l tolerances, can be produced. There is also t h e ability to p r o d u c e p a r t s with aligned fibre reinforcements. SCORIM is carried out on a twin screw injection moulding m a c h i n e w h i c h allows oscillation of t h e hold p r e s s u r e a n d b l e n d i n g / m i x i n g of t h e raw materials. The process a n d its a d v a n t a g e s are discussed. SHRINKAGE D U R I N G REMOVAL OF ORGANIC VEHICLE FROM INJECTION MOULDED ALUMINUM B O D I E S
MJ. Bevis et al, (Brunel University, Uxbridge, UK), Powder Metallurgy, Vol 35, No 2, 1992, 113-116. The use of a polypropylene vehicle for i n j e c t i o n m o u l d i n g of A1 p o w d e r is described. Shrinkage a n d s t r e n g t h of t h e t e s t p a r t s were m e a s u r e d a t i n t e r v a l s d u r i n g t h e d e b i n d i n g operation. As t h e b i n d e r w a s r e m o v e d t h e vol% of A1 increased a n d increases in s t r e n g t h are reported. It is n o t e d t h a t t h e p a c k i n g efficiency is below t h e m a x i m u m value.
PM parts PRODUCTION OF CAMS BY POWDER METALLURGY
Erlagen-Nuremburg,
Erlagen,
Germany),
Powder Metall Int Vol 24, No 5, 1992, 284288. The p r o d u c t i o n of cams from powder is described. Problems arising in p r o d u c t i o n a n d use are discussed. The i m p o r t a n c e of minimizing cost by avoiding t h e use of expensive alloying e l e m e n t s is emphasized. Wear resistance under lubricated conditions ( n o r m a l ) a n d emergency (unlubricated) conditions are taken into account. NEW SYSTEM FOR THE PRODUCTION OF HELICAL GEAR COMPONENTS
H. Good, (Werkzeugbau Alvier AG, Buchs, Switzerland), Powder Metall Int, Vol 24, No 5, 1992, 305. The p r o d u c t i o n of helical gears by a new m e t h o d is described. Modular tooling of t h e p r o c e s s is c o n s i d e r e d . T h e t e c h n i q u e involves r o t a t i o n of t h e tooling to allow s h a p i n g of t h e gear t o o t h profile a n d final sizing.
Miscellaneous S T R U C T U R E S AND MECHANICAL P R O P E R T I E S OF AMORPHOUS ALLOY COMPACTS MADE IN AN INERT ATMOSPHERE
Y. K a w a m u r a et al, (Tohoku University, Sendal, J a p a n ) , J Materials Science, Vol 27, No 4, 1992, 956-962. The use of a n Ar a t m o s p h e r e to reduce oxidation of a n alloy a t all process stages is discussed. The powder was p r o d u c e d by f r a g m e n t a t i o n of a m o r p h o u s r i b b o n s in a p l a n e t a r y ball mill a n d consolidation was by m e a n s of a cubic anvil a p p a r a t u s at high pressures. I t is r e p o r t e d that the c o m p r e s s i v e s t r e n g t h of t h e alloy was increased by 30 to 100% c o m p a r e d with materials p r e p a r e d in air. The alloy used is described as Metglas 2605-2.
F. Vollertsen a n d U. Engel, (University of
MPR March 1993 55