PM High Quality TiB2 from Thermite Reaction Contaminant-free, submicron- sized powders of TiB2 are being produced by self-propagating thermite reactions at the Georgia Institute of Technology, Atlanta, Georgia, USA, according to a report in Advanced Materials and Processes. Ultrafine TiB2 powder can be used in molten-metal-handling, semiconductor and aerospace applications. The material has already been formed into electrodes for smelting aluminium and is being evaluated as a substitute for conventional carbon electrodes. In the Georgia Tech process a heat-resistant container is filled with TiO2, B203 and a reducing agent (A1 or Mg). A wire fuse is inserted in the mixture and resistance heated to a temperature between 600 and 1000°C. The hot wire sets off a highly energetic, self-propagating reaction between the oxides and reducing agent. The reaction produces a composite consisting of TiB2 particles uniformly dispersed in a foam-like aluminium or magnesium oxide matrix. Carbide-free boride powder is produced by dissolving the metal oxide matrix. The conventional method of making TiB2 is expensive and produces large particles that can be contaminated during subsequent size reduction. Georgia Tech claims that its thermite process is also suitable for the preparation of other refractory ceramics including nitrides, silicides, other borides, and silicon, boron, and titanium carbides. Morganite Buys Rigby Rigby Metal Components of Cleckheaton, UK, has been bought by Morganite Special Carbons, a division of the Morgan Crucible multinational. Rigby makes sintered metal components in ferrous, non- ferrous and stainless steel. Morganite already has a small business, Reservoil, operating in a similar field to Rigby. Mr Richard Green, Morgan Crucible's financial planning director, believes that the two firms have complementary product ranges. The two companies will have a combined turnover of £5 million. Last year Morgan Crucible had a turnover of some £520 million. Rigby is being sold by its parent company, Johnson & Firth Brown, the Sheffield, UK, based metals and engineering group for £2.5 million. In the year to September 30, 1989, Rigby made a pre-tax profit of £230 000 on sales of £3.1 million. Sealing porosity in PM parts Ultraseal International of Birmingham, UK, has issued a leaflet to help engineers and designers looking for ways to effectively seal the porosity in powder metal components. It explains the benefits of a new methacrylate process which is claimed to seal the porosity up to the surface of powder metal components in a single treatment. This prevents leakage across the surface when such a component is used under pressure -- for example in a car water pump. The Ultraseal technique (derived from the company's PC 504 process) uses a heat- curing methacrylic sealant which is applied in a vacuum, washes off in plain water and is GAS ATOMIZED POWDER SUPERIOR PERFORMANCE IN NICKEL AND COBALT ALLOYS STAINLESS, HIGH SPEEDAND TOOL STEELS L IdXTL L Strength and reliability in powder technology ANVAL ANVAL P.O. Box 45, S-644 O0 TorsMIla, 301 Rt 17 N Suite 800 Sweden Rutherford NJ 07070 Telephone +46 16 34 98 O0 Phone (201) 939-1065, (800) 99-ANVAL Telex 46011 ANVAL S Fox (20]) 939-1608 Telefax +46 16 35 76 20 MPR October 1990 649
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High Quality TiB2 from Thermite Reaction
Contaminant-free, submicron- sized powders of TiB2 are being produced by self-propagating thermite reactions at the Georgia Institute of Technology, Atlanta, Georgia, USA, according to a report in Advanced Materials and Processes. Ultrafine TiB2 powder can be used in molten-metal-handling, semiconductor and aerospace applications. The material has already been formed into electrodes for smelting aluminium and is being evaluated as a substitute for conventional carbon electrodes. In the Georgia Tech process a heat-resistant container is filled with TiO2, B203 and a reducing agent (A1 or Mg). A wire fuse is inserted in the mixture and resistance heated to a temperature between 600 and 1000°C. The hot wire sets off a highly energetic, self-propagating reaction between the oxides and reducing agent. The reaction produces a composite consisting of TiB2 particles uniformly dispersed in a foam-like aluminium or magnesium oxide matrix. Carbide-free boride powder is produced by dissolving the metal oxide matrix. The conventional method of making TiB2 is expensive and produces large particles that can be contaminated during subsequent size reduction. Georgia Tech claims that its thermite process is also suitable for the preparation of other refractory ceramics including nitrides, silicides, other borides, and silicon, boron, and titanium carbides.
Morganite Buys Rigby Rigby Metal Components of Cleckheaton, UK, has been bought by Morganite Special Carbons, a division of the Morgan Crucible multinational. Rigby makes sintered metal components in ferrous, non- ferrous and stainless steel. Morganite already has a small business, Reservoil, operating in a similar field to Rigby. Mr Richard Green, Morgan Crucible's financial planning director, believes that the two firms have complementary product ranges. The two companies will have a combined turnover of £5 million. Last year Morgan Crucible had a turnover of some £520 million. Rigby is being sold by its parent company, Johnson & Firth Brown, the Sheffield, UK, based metals and engineering group for £2.5 million. In the year to September 30, 1989, Rigby made a pre-tax profit of £230 000 on sales of £3.1 million.
Sealing porosity in PM parts Ultraseal International of Birmingham, UK, has issued a leaflet to help engineers and designers looking for ways to effectively seal the porosity in powder metal components. It explains the benefits of a new methacrylate process which is claimed to seal the porosity up to the surface of powder metal components in a single treatment. This prevents leakage across the surface when such a component is used under pressure - - for example in a car water pump. The Ultraseal technique (derived from the company's PC 504 process) uses a heat- curing methacrylic sealant which is applied in a vacuum, washes off in plain water and is
GAS ATOMIZED POWDER
SUPERIOR PERFORMANCE IN
NICKEL AND COBALT ALLOYS
STAINLESS, HIGH SPEED AND
TOOL STEELS
L IdXTL L Strength and reliability in powder technology
ANVAL ANVAL P.O. Box 45, S-644 O0 TorsMIla, 301 Rt 17 N Suite 800 Sweden Rutherford NJ 07070 Telephone +46 16 34 98 O0 Phone (201) 939-1065, (800) 99-ANVAL Telex 46011 ANVAL S Fox (20]) 939-1608 Telefax +46 16 35 76 20
Mahler sets the Standards :or example: Sintering-forging furnac~ The Mahler sintering-forging
furnace permits dewaxing and sintering of powder metal parts under protective gas at 1120°C with subsequent cooling, or automatic hot discharge for the forging - selectable as desired.
The special advantages of this furnace plant are:
- continuously controllable discharge frequency of the parts, for example 0-400 parts/hour
- conversion of the furnaces from one type of part to another not required
- sintering under carbon-neutral conditions
- oxidation-free cooling under protective gas
- reproducible results
- low space requirement
- low consumption of utilities
Let our specialized engineers provide you with advice.
MAHLER Dienstleistungs-GmbH
Fritz-M011er-Strai3e 95 Postfach 2 86 D-7300 Esslingen/Neckar Telefon (0711) 31623-0 Telex 7256678 mdl d Telefax (0711) 3180513
A member of the Degussa Group
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simply heat cured. The sealant has minimal contraction and thus is claimed not to give a micro-concave surface during curing. This prevents the formation of paths of leakage across the face of the component when it is required to retain fluid under pressure. Sealing the porosity also seals in dust and contaminants which is vital if the component is to be used in a computer disk drive. The leaflet is available from Ultraseal International Ltd, Centurion House, Roman Way, Coleshill, Birmingham B46 1HQ, UK.
Furnace Designed for Processing Powder Compounds Lenton Thermal Designs Ltd of Market Harborough, UK, has announced the development of a furnace system which is designed to provide a variety of operational features necessary for processing powder compounds. The rotary incline tube furnace (RITF) is claimed to be an innovative heat treatment system. It has a maximum operational temperature of 1600°C and a work tube of 80 mm inside diameter. The passage of the powder sample is assisted through the tube during processing by rotating the tube at up to 10 rpm and by inclination with the furnace asssembly to any angle within 0 to 10 ° to the horizontal. There is a variety of options such as a variable-amplitude electromechanicai vibrator, to prevent the accumulation of powder on the inside surface of the work tube. Further options are a hopper screw-feed and facilities for processing in an inert atmosphere.
Mitsubishi Develops Stronger Steel Alloys Two powdered steel alloys for use in the production of highly durable sintered gear-cutting tools have been developed by Mitsubishi Heavy Industries, according to a report in The Wall Street Journal. The two materials, MAC-H and SKH-M have a strength of approximately 400 kg/cm 2, which is twice the strength of conventional alloys. They owe some of their strength to carbide particles that are about one third the diameter of those found in conventional alloys, says Mitsubishi. The company expects sales during the products' first year to reach 1.5 billion yen.
US Bronze Announces New Copper Powders United States Bronze Powders Inc (USB) of Flemington, New Jersey, USA, has announced three new copper and copper
alloy powders for powder metallurgy (PM). M-1000 copper is a water atomized powder, specially processed to achieve lower apparent densities than typical PM powder. It has a high green strength and moderate compressibility, says USB. PM applications include the primary use in friction product formulations, and additions to pre-mix bronze to obtain dimensional stability. Designed for addition to iron powder blends to give a lower effective sintering temperature and for premix bronze powders, M-2000 is a water atomized, irregular copper powder lightly alloyed to provide for lower melting point, high compressibility, moderate green strength and low residual oxide. The third new powder, M-3000, is a water atomized, irregular, pre-alloyed bronze powder with high green strength and lower apparent densities than typical air atomized, pre-alloyed bronze powder. Its PM applications include high density structural parts, additions to premix bronze and iron powder blends to achieve specific metallurgical characteristics of sintered components and also matrix powder for diamond tools.
The rotary incline tube furnace from Lenton is designed for the processing of powders up to 1600°C.
Powder Materials in Transportation
Call for Papers The UK-based Institute of Metals is calling for papers for the PM'91 Powder Metallurgy Group Meeting, 'Powder Materials in Transportation' conference to be held on 21-23 October 1991 in York, UK. The conference will discuss the use of powders and powder metallurgy processes, relating to transportaion by road, rail, sea and air. Authors wishing to submit papers should send a 200-word abstract to The Conference Department (PM), The Institute of Metals, 1 Carlton House Terrace, London SW1Y 5DB, UK, by the end of this year.
Copper Consumption to Rise Copper consumption worldwide will rise at 1.4% a year from 1989 to 2000, according to a report from Roskill Information Services of London, UK. 'The Economics of Copper 1990' says that the most important issue affecting the market for copper is the adoption of fibre optic cable in preference to copper for the transmission of telecommunications signals. However, increased demand for telecommunications channels in the future is likely to maintain the demand for copper wire at a higher level. Consumption of copper scrap is expected to increase faster than the consumption of refined copper from primary sources.
