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Use of cemented carbide as matrix for diamond stud rock drills
Liquid-phase sintering of cermets and graded cemented carbo nitrides L.Chen etal. (SinterMct Inc., Kittanning, USA.) Int. J. Refrac.Me&/Hmd Mater., Vol 18, No 6, 2000, 307,322. Metallurgical reactions and microstructural evolution during liquid phase sintering of cermets and graded cemented carbo-nitrides were investigated by a range of merhods. The multicomponent system Ti-Mo-W-Ta-Nh-(C,N)Co/Ni was studied. Melting characteristics in Tic-MoC/WC-Ni/Co, Tic-TiN-WC-Co and Ti(C,N)-T&-WC-Co were established. Understanding of sintering mechanisms is developed
Use of cemented carbide as matrix for diamond stud rock drills
It is reported that cemented carbide materials had been used as the matrix for diamond rock drills. The WC alloys feature increased work of plastic defrtrmation and ultimate strain. The drills with WC matrix are shown to have increased service life and ability to retain the diamond studs.
Evaluation of thermal shock resistance of tungsten carbide cobalt by laser machining Co., Osaka, Japan.) Metall., Voi 47, No 5,
Thermal shock resistance of WC-Co, ambient temperature, was investigated
Sinter bonding of graded cemented carbide to steel drilling tool K.Tsu& et al. (Sumitomo Electric Industrces, Ltd., Icam, .L-ipan.) .J..&m Sot. Powder/Powder Metail., Vol47, No 5, 2000, 564-568. In Jnpnnese
It is reported that a graded WC-Co layer had been sinter bonded to a steel substrate by pulse-current resistance heating. Stress relief, bond strength and functionality of the coated layer, giving high surface hardness and internal toughness, were confirmed. The application was for drills for oil wells. It is suggested that the new materials should have good performance in deeper wells.
Intermetallic materials Elevated temperature properties of iron aluminide made by metal injection moulding K.Katu,T.Masui. (Nmonai Industrial Research Inst. oj
S.Kouno et ai. (&et Industrial j.]apan SK. Powder/Powder 2000, 553-5.58. In Japanese.
machining with a YAG laser, with reference to WC grain size and %Co. Thermal cracks were found on machined surfaces the number of cracks decreasing with decrease in WC grain size and increase in %Co. Strength was reduced by machining. Results from the laser experiments were compared with wire electrode discharge machining.
at by
Nagoya, Japan ) J Japan Sot. Powder/Powder Voi 47, No 6, 2000, 614,618. inJapanese.
Metall.,
B FeAl (Fe-40at%Al and Fe-48%Al) injection moulded and sintered compacts were tensile tested at ambient temperature, 400, 600 and 800°C in air. At room
temperature Fee48%Al had a tensile strength over 600MPa which diminished with temperature. O.Z%proof stress was 300MPa at 25°C and this was retained at 400 and 600°C. Elongation was 2.3% and 0.3% for Fe-40%Al and Fe-48%Al respectively. Tensile strength of both alloys was lOOMPa at 800°C. There was a brittleiductile transition between 400 and 600°C.
Mechanical alloying Use of mechanical alloying in preparation of metal powders and composite materials I.M.T.Casteilo et al. (Uniwrsity Carlo\ III, Madrid, Spain.) .I Revista Metail. Madrid, Vol 36, No 4, 2000, 279-286. In Spanish.
The mechanical alloying process is reviewed as a means of preparing metal powders. Fundamentals and applications are considered. Use for metal matrix composites and oxide dispersion strengthened alloys is discussed.
PM components Macro-moulds for macro-moulding f.Smith. &ction
Mouldir~g, Vol8, No 7,000, 67-68
It is reported
that Ni powder, made by a vapour deposition process, had been used to make parts, such as cores and cavity shells, for incorporation in very large injection moulding dies for large injection moulded parts. The moulds are shown to have higher strength than steel and to be lighter.
Con repeated forging of bulk alloys. Compaction of powder reached a density of 85%. The two compounds are used as H storage alloys.
Mechanical alloying of chromiumnickel and chromium-manganese steels with high nitrogen
Mechanical alloying Solid state synthesis of magnesium intermetallic compounds with silicon and nickel
It was reported that Mg2Ni and Mg2Si had been synthesized from elemental powders by mechanical alloying and could be attained in 2% of the time required for production be
38
MPR December
2001
Production of Cr.Ni and Cr-Mn steels, with up to 9.85wt%N, by mechanical alloying was described. Results of X-ray and magnetic tests were presented. N was shown to enhance stabilization of austenite. Hot rolling, at 700 to lOOO”C, enable production of fully dense alloys with the nano-structure retained. Formation of detrimental CrN was avoided.
Structure and properties of fine-graded steel with dispersed titanium dioxide
Fe alloys, with dispersed TiO2, were made by mechanical alloying, which yielded an ultrafine microstructure after 100 hours. After he&t treatment at 1000°C the body-centred cubic matrix had a grain size of 200 to 500mm with Ti02 particles evenly dispersed in grain boundaries. Fe,(4wt%Ti-0.5%0) had a 0.2% proof stress of l.OGPa, ultimate tensile strength of 1.2G Pa and 10% elongation ar ambient temperature. Microstructures and precipitation characteristics of TiO2 were discussed.
www.metal-powder.net
Use of cemented carbide as matrix for diamond stud rock drills
It is reported that cemented carbide materials had been used as the matrix for diamond rock drills. The WC alloys feature increased work of plastic defrtrmation and ultimate strain. The drills with WC matrix are shown to have increased service life and ability to retain the diamond studs.
Evaluation of thermal shock resistance of tungsten carbide cobalt by laser machining Co., Osaka, Japan.) Metall., Voi 47, No 5,
Thermal shock resistance of WC-Co, ambient temperature, was investigated
Sinter bonding of graded cemented carbide to steel drilling tool K.Tsu& et al. (Sumitomo Electric Industrces, Ltd., Icam, .L-ipan.) .J..&m Sot. Powder/Powder Metail., Vol47, No 5, 2000, 564-568. In Jnpnnese
It is reported that a graded WC-Co layer had been sinter bonded to a steel substrate by pulse-current resistance heating. Stress relief, bond strength and functionality of the coated layer, giving high surface hardness and internal toughness, were confirmed. The application was for drills for oil wells. It is suggested that the new materials should have good performance in deeper wells.
Intermetallic materials Elevated temperature properties of iron aluminide made by metal injection moulding K.Katu,T.Masui. (Nmonai Industrial Research Inst. oj
S.Kouno et ai. (&et Industrial j.]apan SK. Powder/Powder 2000, 553-5.58. In Japanese.
machining with a YAG laser, with reference to WC grain size and %Co. Thermal cracks were found on machined surfaces the number of cracks decreasing with decrease in WC grain size and increase in %Co. Strength was reduced by machining. Results from the laser experiments were compared with wire electrode discharge machining.
at by
Nagoya, Japan ) J Japan Sot. Powder/Powder Voi 47, No 6, 2000, 614,618. inJapanese.
Metall.,
B FeAl (Fe-40at%Al and Fe-48%Al) injection moulded and sintered compacts were tensile tested at ambient temperature, 400, 600 and 800°C in air. At room
temperature Fee48%Al had a tensile strength over 600MPa which diminished with temperature. O.Z%proof stress was 300MPa at 25°C and this was retained at 400 and 600°C. Elongation was 2.3% and 0.3% for Fe-40%Al and Fe-48%Al respectively. Tensile strength of both alloys was lOOMPa at 800°C. There was a brittleiductile transition between 400 and 600°C.
Mechanical alloying Use of mechanical alloying in preparation of metal powders and composite materials I.M.T.Casteilo et al. (Uniwrsity Carlo\ III, Madrid, Spain.) .I Revista Metail. Madrid, Vol 36, No 4, 2000, 279-286. In Spanish.
The mechanical alloying process is reviewed as a means of preparing metal powders. Fundamentals and applications are considered. Use for metal matrix composites and oxide dispersion strengthened alloys is discussed.
PM components Macro-moulds for macro-moulding f.Smith. &ction
Mouldir~g, Vol8, No 7,000, 67-68
It is reported
that Ni powder, made by a vapour deposition process, had been used to make parts, such as cores and cavity shells, for incorporation in very large injection moulding dies for large injection moulded parts. The moulds are shown to have higher strength than steel and to be lighter.
Con repeated forging of bulk alloys. Compaction of powder reached a density of 85%. The two compounds are used as H storage alloys.
Mechanical alloying of chromiumnickel and chromium-manganese steels with high nitrogen
Mechanical alloying Solid state synthesis of magnesium intermetallic compounds with silicon and nickel
It was reported that Mg2Ni and Mg2Si had been synthesized from elemental powders by mechanical alloying and could be attained in 2% of the time required for production be
38
MPR December
2001
Production of Cr.Ni and Cr-Mn steels, with up to 9.85wt%N, by mechanical alloying was described. Results of X-ray and magnetic tests were presented. N was shown to enhance stabilization of austenite. Hot rolling, at 700 to lOOO”C, enable production of fully dense alloys with the nano-structure retained. Formation of detrimental CrN was avoided.
Structure and properties of fine-graded steel with dispersed titanium dioxide
Fe alloys, with dispersed TiO2, were made by mechanical alloying, which yielded an ultrafine microstructure after 100 hours. After he&t treatment at 1000°C the body-centred cubic matrix had a grain size of 200 to 500mm with Ti02 particles evenly dispersed in grain boundaries. Fe,(4wt%Ti-0.5%0) had a 0.2% proof stress of l.OGPa, ultimate tensile strength of 1.2G Pa and 10% elongation ar ambient temperature. Microstructures and precipitation characteristics of TiO2 were discussed.
www.metal-powder.net