New edition of international PM directory released

New edition of international PM directory released

Ball mill designed for mechanical alloying role A BALL mill developed specifically for mechanical alloying applications has been added to the product ...

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Ball mill designed for mechanical alloying role A BALL mill developed specifically for mechanical alloying applications has been added to the product range of UK c omp an y Glen Creston of Stanmore. The company says the 'Uni Ball Mill' allows the synthesis of a wide variety of entirely new alloys and composites. Milling conditions can be reproduced since milling programmes can be stored in the unit's memory and re-run. Whereas traditional ball mills feature chaotic ball motion to alloy metal powders, the Uni Ball Mill allows milling energy to be controlled. This is achieved by varying the location and intensity of high power peripheral magnets, by changing rotational speed and by changing the number and size of balls inside the chambers. Four samples can be run simultaneously in separate chambers, each with independent heating control up to 200°C and with selected atmospheres within each chamber. A cooling bath is available for milling below ambient temperature. Milling p a r a m e t e r s are easily entered into a microprocessor and are displayed on L C D screens.

Niokel plated bonded magnets developed

N e w ed/tion of

International PM directory released

Also new to Glen Creston's product range is the Dual Mixer Mill 8000D. This unit pulverizes hard, brittle samples in the 10 gram range and complements the M.280 Single Mixer Mill. It is suitable for preparing samples of hard materials, such as tungsten carbide and chromium, prior to spectroscopic techniques. Incorporating two mixing vials, the mill prepares samples to analytical requirements. The sealed vials are shaken at high speed in a three-dimensional figure-ofeight motion. The sample is both pulverized and mixed by the resulting impact of a grinding ball. The use of dual vials not only increases the quantity of sample being processed, but Glen Creston says it also ensures the machine operates in a balanced mode, reducing vibration and extending the unit's operating life. Another feature of the mill is the incorporation of integral cooling fans which allow increased grinding time to accommodate mechanical alloying samples.

N I C K E L plated neodymiumiron-boron bonded magnets offering better rust resistance have been developed by Kaneka Corp. The magnets will be targeted at manufacturers of hard disc drives and automotive motors. Conventional bonded magnets, which are highly susceptible to rust, are ordinarily coated with resins which can eventually be penetrated by moisture. Mechanical strength of conventional magnets is also insufficient.Kaneka succeeded in reformulating a plating material so that it could be used to treat the surface of the new bonded magnet. In 48-hour pressure-cooker tests at 110°C and two atmospheres of pressure, no changes were detected and the magnets were estimated to be more than four times as durable as magnets coated with resins. The outside diameters of the magnets range from 8-10 mm, while t h e i r m a g n e t i c s t r e n g t h from 9-10 megagausses. Marketing is aimed mainly at makers of hard disc drives and automotive motors.

T H E 8th edition of the International Powder Metallurgy Directory has been released enabling users to find the powder producer, equipment supplier or component maker of their choice worldwide. The latest edition of this popular reference contains the latest information on PM in 56 countries with each entry detailing the products made or the services offered. It also lists relevant trade associations, research centres and consultants. An introductory article outlines the PM process and its applications. Published in January 1994, the 217 page directory is now in an A4 format and contains for the first time contact details for several companies in China, the countries of the former Soviet Union and Easteru Europe. It also contains updated postcodes for German companies which were introduced in July 1993. Pree with the 8th edition is an electronic version of the directory for use on any IBM or compatible computer which greatly simplifies company or product searches.

Glen Creston; tel: + 44-812060123; fax: + 44-812062452.

Kaneka Carp; tel: + 81-6226-5050; faT: + 81-6-226517Z (c)

MPR Publishing Services Ltd; tel: +44-743-364675; faT: + 44-743-362968.

Hugan Ltd completes Far East contract for p r e s s tools H U G A N Ltd, a powder metallurgy (PM) consultaney based in London, UI~ has recently completed a contract to supply a set of compacting and sizing press equipment to the Peoples Republic of China The contract involved the design and manufacture of over 12 dies sets fully equipped with punches, dies and cores rods, together with the same number of dedicated p r o g r a m m a b l e logic controlled (PLC) compacting and sizing presses. Materials, tool tolerances and surface finishes had to be chosen to enable tool maintenance to be carried out by semi-skilled operators in remote areas. To meet these challenges, Hugan took full advantage of the latest advances in special tool steels specifically formulated for the P M industry in

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the design of punches, core rods and other parts. The materials selected included Vanadis 4 and A S P 23 (Uddeholm of Bohler equivalents) for optimum hardness and toughness yielding 62-64Rc for the top and bottom punches, all surface finishes in contact with P M polished to 0.02 1to mirror finish by use of 2-3 p_m diamond lapping compound. The multi-platen die sets, made of 1.5% NiCrMo are of conventional three plate x four pillar design to handle 2-4 level compacts, each die set having a eyllnder-operated powder feed shoe and standardized clamp rings and K40 tungsten carbide guide bushes for extra long life. Additionally, these modular die sets are arranged to accept an unlimited number of punch

sets and core rods, so long as the punch spigots and die casings lie within the 30 nun x 8 m m x 70 m m and 75 nun x 40 nun formats respectively. The die sets are required to run continuously at 55-60 strokes per minute in 20 hour shifts. The subsequent green compacts pass through a belt conveyor sintering furnace for dewaxing and heat treatment between 780-810°C for 15 minutes before passing through a vacuum impregnation station. A quality assurance programme ensures that each part is checked for concentricity, surface finish and hardness. The parts are also cleaned, cheek-weighed, counted and labelled before being dispatched. At the moment, t h e Chinese are using the equipment to produce self-lubricat-

ing bearings from copper powder. Hugan says no UK press manufacturer could offer to meet the specification for a complete turnkey process line, especially the high speed output requirement for the bulk powder handling, conveying and automatic gauging. This necessitated the consultancy importing and reengineering of a number of European presses, which involved retrofittingthem with a new design of hydraulic upthrust actuator for the bottom sleeve punch delay cycle and designing a suitable PLC sequencing control installation to meet the high output rate. Hugan is currently negotiating a second contract to the region.

H. E. W~Uiamson, Hugan l_4d,, tel: + 44-81-5466169.