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Preparation of metastable Yttrium and Dysprosium Sulphides by mechanical alloying (MA) and mechanical milling
Ta p o w d e r s w i t h 30at% A1 were subjected to rod milling to produce amorphous powders. The powders were characterized and were shown to have low levels of contamination and to have high thermal stability.
MECHANICAL ALLOYING (MA) SPREADS ITS WINGS JJ. Fischer, J.H. Weber, (Inco Alloys International, USA), Advanced Materials and Processes, Vol 138, No 4, 1990, 48-50. The process of MA is reviewed with respect to its range of applications. Oxide dispersion strengthened (ODS) Al alloys and Ni base superalloys for ~ e and gas turbine uses are considered. Future developments for M A materials are discussed. E x a m p l e s given include metastable phases, amorphous materials, cermets and materials with non-metallic matrices.
PREPARATION OF METASTABLE YTTRIUM AND DYSPROSIUM SULPHIDES BY MECHANICAL ALLOYING (MA) AND MECHANICAL MILLING S.H. Han et al, (Iowa State Unlv, Ames, Iowa, USA), Scripta Metallurgica Materbzlia, Vol 24, 1990, 295-298. The use of MM and MA to prepare metastable 7Y2Ss and Dy2Ss, for application as t h e r m o e l e c t r i c m a t e r i a l s , for temperature measurement and control, is described.
95.1% and the carbon and oxygen contents were 0.001% and 0.03wt% respectively. DURING BALL MILLING
Mlsc~bneous N. Merk, L.E. Tanner, (L. Berkeley I~boratory, Berkeley, California, USA), Scr/pta MetaUu~ica Matfcialia, Vol 24, 1990, 309313. Mixtures of Ni-25at%Ta and Ni-50%'ra elemental powders were subjected to high energy ball milling in a planetary mill in argon for 20 hours using WC-Co crushing bodies. The powders were characterized to determine the extent of amorphization and contamination. Severe contamination from the crushing balls was found and this was attributed to the low ductility of the WC-Co.
Metal injection moulding BINDER EXTRACTION AND SINTERING OF METAL INJECTION MOULDING (MIM) OF STAINLESS STEEL PARTS K. Saitoh, Y. Kaneko, (Ritsumeikan Univ, Kyoto, Japan), J. Soc. Matez~ls Science of Japan, Vol 39, No 442, 1990, 844-846, (In Japanese). 316L stainless steel powder was mixed with a binder consisting of polyetbyiene (PE), polypropylene (PP) and sesame oil (SO) and injection moulded. The SO was removed from the green compact by immersion in tetrahydrofuran at 50°C for 2 hours. The polymers were removed by heating in N2 and the bebound parts were vacuum sintered at 1320°C for 1 hour. The relative density of the sintered parts was
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EFFECTS OF PHYMCO-CHEMICAL FACTORS ON M DISTRIBUTION OF FINE METAL PARTICLES IN EPOXY RESIN MATRIX M.M. Kkvorov et al, Poroshkovaya Metallu~tiya, No 1, 1991, 89-93, (In Russian). The distribution of metal powders, Fe, Ni and Cu, in a solidified epoxy resin matrix has been determined as a function of process variables. It was shown that modification of the metal powder surfaces resulted in a more uniform structure and more stable metal/epoxy resin composite. THE DYNAMICS OF POWDER METALLURGY D.G. White, (MPIF/AMPI, Princeton, New Jersey, USA), Industrial Heating, Vol 57, No 8, 1990, 32-33. A forecast is made that the PM industry is likely to expand by 6 to 10% as increased use is made of P M parts in engineering, particularly the automotive industry. Technological developments axe discussed. Greater increase in the use of ferrous, rather than non-ferrous, materials is predicted and the use of new processes, such as metal injection moulding, is also expected to increase. It was reported that a P M stainless steel, 316L, has been given approval by the U S National Association of Corrosion Engineers.
1991 AMPI/MPIF P o w d e r Metallurgy Conference. The f o l l o w i n g abstracts are o f papers p r e s e n t e d at the c o n f e r e n c e held in Chicago, Illinois, USA, 9 to 12 June, 1991. A further s e l e c t i o n will b e included in the n e x t issue.
POWDEN PMODUCIrION INFLUENCE OF ALIA)YING ON THE
PROPERTIES OF WATER ATOMIZED COPPER POWDERS JJ. Dunkley et al, (Davy McKee (Sheffield) Ltd, Sheffield, UK). Results of the determination of the effects of various alloy additions, in the range 0 to 10%, on the properties of water atomized Cu alloy powders, size and size distribution, particle shape and 0 content were presented. The results were analysed in the light of earlier work.
FUNDAMENTAL8 OF HIGH PRESSURE GAS ATOMIZATION I.E. Anderson, R.S. Flgiola, (Iowa State Unlv, Iowa, USA).
The p a p e r p r e s e n t e d r e s u l t s of measurements of gas and molten metal fluid dynamics in high pressure gas atomization, particularly close to the melt tube orifice. Various sensor a c t u a t o r combinations were suggested for on-line m e a s u r e m e n t s and control of process parameters. Aspects of atomizer system design considered included powder transport, separation and collection. ADVANCED SENSORS AND PROCESS CONTROL FOR GAS ATOMIZATION S.D. Riddler et al, (National Inst of Standards and Technology, USA). T h e intelligent control of gas atomization was discussed with regard to parameters which relate to process control including fluid dynamics and particle size s e n s i n g and e x p e r i m e n t a l work was described. A modular process control system incorporating the results of the studies was described.
METALLURGICAL EXAMINATION OF NEW STEEL POWDERS S.M. Kaufman, S.E. LeBeau, (Phoenix Metals Corp, Plymouth, Michigan, USA). An investigation of the properties of mechanically ground steel powder was described. Results for loose powders and final dimensions, strength and hardness of a range of powder blends, sintered under a range of c o n d i t i o n s , were reported. Micrographs of powders and sintered materials were shown. The properties of the steel powders were compared with those of ordinary iron powder.
PRODUCTION OF HIGH QUALITY IRON POWDER FROM SYI)VARANGER IRON ORE J.H. Ulvensoen et al, (SINTEF Metallurgy, Norw~).
MPR July/August 1991 59
MECHANICAL ALLOYING (MA) SPREADS ITS WINGS JJ. Fischer, J.H. Weber, (Inco Alloys International, USA), Advanced Materials and Processes, Vol 138, No 4, 1990, 48-50. The process of MA is reviewed with respect to its range of applications. Oxide dispersion strengthened (ODS) Al alloys and Ni base superalloys for ~ e and gas turbine uses are considered. Future developments for M A materials are discussed. E x a m p l e s given include metastable phases, amorphous materials, cermets and materials with non-metallic matrices.
PREPARATION OF METASTABLE YTTRIUM AND DYSPROSIUM SULPHIDES BY MECHANICAL ALLOYING (MA) AND MECHANICAL MILLING S.H. Han et al, (Iowa State Unlv, Ames, Iowa, USA), Scripta Metallurgica Materbzlia, Vol 24, 1990, 295-298. The use of MM and MA to prepare metastable 7Y2Ss and Dy2Ss, for application as t h e r m o e l e c t r i c m a t e r i a l s , for temperature measurement and control, is described.
95.1% and the carbon and oxygen contents were 0.001% and 0.03wt% respectively. DURING BALL MILLING
Mlsc~bneous N. Merk, L.E. Tanner, (L. Berkeley I~boratory, Berkeley, California, USA), Scr/pta MetaUu~ica Matfcialia, Vol 24, 1990, 309313. Mixtures of Ni-25at%Ta and Ni-50%'ra elemental powders were subjected to high energy ball milling in a planetary mill in argon for 20 hours using WC-Co crushing bodies. The powders were characterized to determine the extent of amorphization and contamination. Severe contamination from the crushing balls was found and this was attributed to the low ductility of the WC-Co.
Metal injection moulding BINDER EXTRACTION AND SINTERING OF METAL INJECTION MOULDING (MIM) OF STAINLESS STEEL PARTS K. Saitoh, Y. Kaneko, (Ritsumeikan Univ, Kyoto, Japan), J. Soc. Matez~ls Science of Japan, Vol 39, No 442, 1990, 844-846, (In Japanese). 316L stainless steel powder was mixed with a binder consisting of polyetbyiene (PE), polypropylene (PP) and sesame oil (SO) and injection moulded. The SO was removed from the green compact by immersion in tetrahydrofuran at 50°C for 2 hours. The polymers were removed by heating in N2 and the bebound parts were vacuum sintered at 1320°C for 1 hour. The relative density of the sintered parts was
llll
l
IIIII
EFFECTS OF PHYMCO-CHEMICAL FACTORS ON M DISTRIBUTION OF FINE METAL PARTICLES IN EPOXY RESIN MATRIX M.M. Kkvorov et al, Poroshkovaya Metallu~tiya, No 1, 1991, 89-93, (In Russian). The distribution of metal powders, Fe, Ni and Cu, in a solidified epoxy resin matrix has been determined as a function of process variables. It was shown that modification of the metal powder surfaces resulted in a more uniform structure and more stable metal/epoxy resin composite. THE DYNAMICS OF POWDER METALLURGY D.G. White, (MPIF/AMPI, Princeton, New Jersey, USA), Industrial Heating, Vol 57, No 8, 1990, 32-33. A forecast is made that the PM industry is likely to expand by 6 to 10% as increased use is made of P M parts in engineering, particularly the automotive industry. Technological developments axe discussed. Greater increase in the use of ferrous, rather than non-ferrous, materials is predicted and the use of new processes, such as metal injection moulding, is also expected to increase. It was reported that a P M stainless steel, 316L, has been given approval by the U S National Association of Corrosion Engineers.
1991 AMPI/MPIF P o w d e r Metallurgy Conference. The f o l l o w i n g abstracts are o f papers p r e s e n t e d at the c o n f e r e n c e held in Chicago, Illinois, USA, 9 to 12 June, 1991. A further s e l e c t i o n will b e included in the n e x t issue.
POWDEN PMODUCIrION INFLUENCE OF ALIA)YING ON THE
PROPERTIES OF WATER ATOMIZED COPPER POWDERS JJ. Dunkley et al, (Davy McKee (Sheffield) Ltd, Sheffield, UK). Results of the determination of the effects of various alloy additions, in the range 0 to 10%, on the properties of water atomized Cu alloy powders, size and size distribution, particle shape and 0 content were presented. The results were analysed in the light of earlier work.
FUNDAMENTAL8 OF HIGH PRESSURE GAS ATOMIZATION I.E. Anderson, R.S. Flgiola, (Iowa State Unlv, Iowa, USA).
The p a p e r p r e s e n t e d r e s u l t s of measurements of gas and molten metal fluid dynamics in high pressure gas atomization, particularly close to the melt tube orifice. Various sensor a c t u a t o r combinations were suggested for on-line m e a s u r e m e n t s and control of process parameters. Aspects of atomizer system design considered included powder transport, separation and collection. ADVANCED SENSORS AND PROCESS CONTROL FOR GAS ATOMIZATION S.D. Riddler et al, (National Inst of Standards and Technology, USA). T h e intelligent control of gas atomization was discussed with regard to parameters which relate to process control including fluid dynamics and particle size s e n s i n g and e x p e r i m e n t a l work was described. A modular process control system incorporating the results of the studies was described.
METALLURGICAL EXAMINATION OF NEW STEEL POWDERS S.M. Kaufman, S.E. LeBeau, (Phoenix Metals Corp, Plymouth, Michigan, USA). An investigation of the properties of mechanically ground steel powder was described. Results for loose powders and final dimensions, strength and hardness of a range of powder blends, sintered under a range of c o n d i t i o n s , were reported. Micrographs of powders and sintered materials were shown. The properties of the steel powders were compared with those of ordinary iron powder.
PRODUCTION OF HIGH QUALITY IRON POWDER FROM SYI)VARANGER IRON ORE J.H. Ulvensoen et al, (SINTEF Metallurgy, Norw~).
MPR July/August 1991 59