Effect of Ni on grain growth in W wire

Effect of Ni on grain growth in W wire

Effect of sintering temperature, Ni concentration (1-20%) and test temperature on microhardness of Mo-Ni alloys investigated. Statistics applied to th...

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Effect of sintering temperature, Ni concentration (1-20%) and test temperature on microhardness of Mo-Ni alloys investigated. Statistics applied to the results of microhardness testing and effects of test temp e r a t u r e on m i c r o h a r d n e s s . G o o d agreement between measured and predicted data claimed.

target materials. It is concluded that PM p r o v i d e s a s u i t a b l e m e t h o d for the production of sputtering targets in W10%Ti.

PM parts

HIGH TEMPERATURE MECHANICAL P R O P E R T I E S OF W-2%Re P M ALLOY

STATUS OF P M S T R U C T U R A L PARTS USED IN A U T O M O T I V E APPLICATIONS

O.G. Radchenko, et al, Poroskovaya Metallurgia, 1989, No 11, 31-35. In Russian Strength and plasticity of W-2%Re alloy c o m p a r e d w i t h u n al lo y e d W and W reinforced with oxides and carbides. Before testing alloys were rolled to a total strain of 93%. It was shown that the Re alloy has greater high temperature strength than unalloyed W and alloys strengthened by additions of Y and Hf oxides.

H. Fengiin, (Beijing Industrial Company of Powder Metallurgy, China), PM Technology, Vol 8, No 2, 1990, 99-113. In Chinese The use of PM in the manufacture of components for automotive applications in engine, transmission, steering systems and other parts is systematically reviewed. The paper shows the growth in the use of PM parts.

R O L L I N G OF Mo AND W WIRE IN GROOVED ROLLS L.A. Barkov, Poroskovaya MetaUurgia, 1989, No 11, 91-96. In Russian Rolling of Mo and W billets in grooved rolls as an alternative to swaging is d i s c u s s e d . 3 - r o l l Kocks a n d 4 - r o l l Chelyabinsk mills are described and their potential reviewed. Design of a continuous mill with 3-roll and 4-roll passes is described. Advantages and disadvantages of both swaging and rolling are discussed. A M IN E T U N G S T A T E S AND T H E I R A P P L I C A T I O N F OR W P O W D E R PRODUCTION Z. Zhiqiang, et al, (PM Research Institute, CSUT, Changsha, Hunan, China), Int J. Refractory Metals & Hard Materials, Vol 9, No 3, 1990, 143-145 A literature review of amine tungstates is presented. The potential use of these compounds in the production of W metal, as an alternative to the use of ammonium paratungstate, is discussed. D E V E L O P M E N T OF W-Ti BINARY ALLOY S P U T T E R I N G TARGETS AND STUDY O F T H E S P U T T E R I N G CH A RA C T ER I S TI C S M. Yamauchi, T. Kibayashi, (Nippon Tungsten Co, Fukuoka, Japan), Int J. Refractory Metals & Hard Materials, Vol 9, No 3, 1990, 146-153 The production of W-10%Ti, for use as sputtering targets, by 3 methods was investigated. The methods were conventional pressing and sintering, hot pressing and a special sintering process. The last of these was considered to be the most suitable for the purpose. Films were sputtered on to a MgO substrate and the v a r i o u s p a r a m e t e r s e x a m i n e d . The sputtered films were compared with the

& Hard Materials, Vol 9, No 2, June 1990, 104-108 The microalloying of tantalum with silicon has been effectively used on a commercial scale. However, data on effects of m i c r o a l l o y i n g on p r o c e s s i b i l i t y , microstructure and mechanical properties is not readily available. Ta powder with several levels of silicon (0-50 ppm) was processed under identical conditions; sheet s a m p l e s were a n n e a l e d at d i f f e r e n t temperatures and evaluated via microstructural, chemical and mechanical tests. The recrystallization temperature increased with silicon content. It is most probably due to the presence of an intermetallic (Ta3Si) phase. The mechanical properties of unrecrystallized tantalum, are expectedly, significantly different from those of recrystallized tantalum.

S T E A M T H E R M A L OXIDATION OF P M PARTS

MISCELLANEOUS

V. T. Kofee, et al, Poroskovaya Metailurgia, 1989, No 9, 90-94. In Russian Steam thermal oxidation of automotive components is described. Variations in the p r o p e r t i e s of o x i d a t i o n p r o d u c t s of different composition are studied. Spoilage and the reasons for this are discussed.

TECH N I CA L AND E C O N O M I C C O N S I D E R A T I O N S OF P M SUPERALLOYS

P O W D E R METALLURGY IN GEAR M A N U F A C T U R E - A REVIEW S.D.I~ Saheb, K. Gopinath, (Indian Institute of Technology, Madras, India), Powder Metallurgy Science & Technology, Vol 1, No 4, 1990, 43-66 The paper traces the development of the u s e o f PM in g e a r p r o d u c t i o n . I m p r o v e m e n t s in t h e p r o c e s s a r e discussed and it is shown how these have led to the production of components with higher and more uniform densities, better dimensional control and enhanced mechanical properties. The advantages gained by use of PM are outlined.

Tungsten inlllllr

EFFECT OF Ni ON GRAIN G R O W T H IN W WIRE I.H. Moon et al, (Hail Yang University, Korea). J Less Common Metals, Vol 153, No 2, 1989, 275-283 Measurements made of grain growth rate in W wire with addit$ons of Ni. Sintering was at 1400°C. Ni found to accelerate grain growth. EFFECT OF M I C R O A L L O Y I N G W I T H S I L I C O N ON T H E P R O P E R T I E S OF TANTALUM K.D. Moser et al, (Cabot Corp, Boyertown, PA, USA), Int. Journal of Refi'actory Metals

L.W. Lherbier, W.B. Kent (Cytemt Powder Products, Bridgeville, Penn, USA) Int J Powder Metallurgy, Vol 26, No 2, 1990, 131-137. PM superalloys play a critical role in many gas turbine engines. Examples of parts in service include turbine and compressor disks, blade retainers and cooling plates. The materials have been c h o s e n by v i r t u e of t h e i r u n i q u e combination of strength, creep and fatigue characteristics within the operating temperature regime of today's advanced engines. The purpose of this paper is to characterize the current status of PM superalloy technology from both the t e c h n i c a l and e c o n o m i c v i e w p o i n t s . Technical and economic issues have been identified and alternatives suggested for expanding the use of PM superalloys in present and future gas turbine engine systems. P M IN TAIWAN T.T. Wang, C.L. Chu (Taiwan Porite Co, Chu Nun, Taiwan), Int J Powder Metallurgy, Vol 26, No 2, 1990, 167-169 Development, present status, trends in the PM industry of Talwan and research institutes are reviewed. Current activities include production of powders, parts and bearings, magnetic materials and cemented carbides. ASPECTS OF P O W D E R T E C H N O L O G Y IN ANCIENT AND MEDIEVAL INDIA R.K. Dube, (Indian Inst. of Technology, Kanpur, India), Powder Metallurgy, Vol 33, No 2, 1990, 119-125

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