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Wetting of binary aluminium alloys in contact with Be, B4C and graphite
MANNING, C. R. and GURGANUS, T.B.
Wetting of binary aluminium alloys in contact with Be, B4C and graphite
Journal o f the American Ceramic Society, 52, No 3, p 115 (1969) The wetting o f Be, BaC and graphite by liquid binary alloys of A1 with Si, Cu, Mg, Mn, Bi, and Pb was measured in vacuum and helium using the sessiledrop technique. The angle of contact of the liquid alloys on the solid was 100 ° for all the liquid/solid combinations except for A1-20% Mg on Be which gave an angle of 68 ° . Angles of contact close to zero were achieved on graphite however by prior coating of the graphite with Ti. It was concluded that most of these combinations would be unsuitable as the bases of composite materials produced by liquid-phase sintering unless the filaments could be coated with a material that readily bonds with the Al-alloy matrix. (10 references) (69/3/7)
alumina or zirconia as dispersoid. The alloys were then forged and cold rolled. After sintering at 1350°C the working resulted in rounded dispersoid particles in the A1203 alloys but angular particles in the ZrO2 alloys. The ultimate tensile strengths in the latter alloys were markedly lower than in the former. After sintering at 1200°C the working produced rounded particles in both sets of alloys and there was little difference in the strengths. Extrusion at 1000°C, instead of forging and rolling, produced near-spherical particles after either sintering temperature in b o t h sets of alloys and again there was little difference in strength. The mechanical properties of the extruded alloys were measured up to 600°C and found to agree with known isochronal recrystallisation data. (5 references) (69/3/9)
SHETTY, M. N.
Plastic deformation of large copper whiskers at different temperatures and strain rates NEWS ITEM
Tungsten coated carbon fibres
Nature, 222, No 5198, p 1021 (June
1969) The Fulmer Research Institute has coated carbon fibre with thin tungsten films by vapour deposition. These may be used to reinforce metal matrices for use up to 1000°C. Main disadvantages are the high density of tungsten and its tendency to form brittle tungsten carbide during prolonged high temperature usage. There is also interest in aluminium coated fibres which could be used up to 400°C but would have neither of these drawbacks. (69/3/8)
SINGH, B. N., COTTERILL, P. and WALDRON, M. B.
The effect of dispersoid properties on the dispersion strengthening of carbonyl iron
Powder Metallurgy, 12, No 23, p 157
(1969) It was shown experimentally that the mechanical properties of dispersion strengthened Fe depend on the dispersoid particle shape as well as part i d e size and separation. Alloys were prepared b y sintering carbonyl Fe, containing different amounts of
62 COMPOSITES September 1969
Transactions AIME, 245, p 880 (1969) Copper whiskers of between 70 and 100 microns diameter and of different orientations were grown from CuI by reduction with H2 at 500°C and subjected to tensile testing at temperatures from 77 ° to 473°K. The temperature dependence of flow stress was similar to that of bulk single crystals. In general the results suggested a high grown-in dislocation density. (16 references) (69/3/10)
STOLARZ, VON ST, GOLONKA, J. and KURZEJA, J.
The technology of production of sintered single- and multi-layer contact bushes of W-Cu-Ni alloys
Planseeberichte fur Pulvermetallurgie, 17, p 10 (1969) Techniques were investigated for the production of contact bushes from W-Cu and W-Cu-Ni alloys using the infiltration method and/or liquid phase sintering. The effects of production conditions on the properties of the bushes were studied. As well as producing bushes of a single alloy, it was possible to prepare bushes consisting of layers of alloys of different composition. Methods of brazing the
latter to supports are described. (14 references) (69/3/11)
WILCOX, B. A. and CLAUER, A. H.
Tensile and creep deformation of a fiber reinforced Mg-Li alloy
Transactions AIME, 245, p 945 (1969) Reinforcement of a Mg-14wt% Lilwt% A1 alloy matrix with continuous wires of precipitation hardened stainless steel resulted in a significant increase in ultimate strength and strength-to-density ratio, from room temperature up to 200°C. The ultimate strength of the composite was lower than the value predicted by the law of mixtures. It was considered that this was due to some misalignment of the wires. The creep of the composite and of the free wires was logarithmic whereas the unreinforced matrix alloy exhibited steady state creep behaviour. It was concluded that the creep of the wires controlled the creep of the composite. A relationship existed between the creep rate, e, of the composite and the average tensile stress on the fibres, 5f, such that ~rv(of) 3 4. (12 references) (69/3/12)
Resin matrices ATKINSON, H. E.
Engineering basis for RP chemicalresistant tanks
Modern Plastics, 46, 6, p 108 (June 1969) Composite specimens of potential tank materials were made up from various combinations of E and C glass mat and roving in epoxy and polyester resin systems to meet the demands of tests under total immersion or one-side exposure conditions in hostile environments. The effects of chemical attack on mechanical properties, stress on chemical resistance and temperature on strength retention are reported and fabrication techniques relevant to good performance are reviewed. (69/4/1) BILBE, W. G.
Designing with PTFE
Engineering, Materials and Design, 12, No 6, p 871 (June 1969} A general review article on the uses of PTFEmentions a new product (Forma-
Wetting of binary aluminium alloys in contact with Be, B4C and graphite
Journal o f the American Ceramic Society, 52, No 3, p 115 (1969) The wetting o f Be, BaC and graphite by liquid binary alloys of A1 with Si, Cu, Mg, Mn, Bi, and Pb was measured in vacuum and helium using the sessiledrop technique. The angle of contact of the liquid alloys on the solid was 100 ° for all the liquid/solid combinations except for A1-20% Mg on Be which gave an angle of 68 ° . Angles of contact close to zero were achieved on graphite however by prior coating of the graphite with Ti. It was concluded that most of these combinations would be unsuitable as the bases of composite materials produced by liquid-phase sintering unless the filaments could be coated with a material that readily bonds with the Al-alloy matrix. (10 references) (69/3/7)
alumina or zirconia as dispersoid. The alloys were then forged and cold rolled. After sintering at 1350°C the working resulted in rounded dispersoid particles in the A1203 alloys but angular particles in the ZrO2 alloys. The ultimate tensile strengths in the latter alloys were markedly lower than in the former. After sintering at 1200°C the working produced rounded particles in both sets of alloys and there was little difference in the strengths. Extrusion at 1000°C, instead of forging and rolling, produced near-spherical particles after either sintering temperature in b o t h sets of alloys and again there was little difference in strength. The mechanical properties of the extruded alloys were measured up to 600°C and found to agree with known isochronal recrystallisation data. (5 references) (69/3/9)
SHETTY, M. N.
Plastic deformation of large copper whiskers at different temperatures and strain rates NEWS ITEM
Tungsten coated carbon fibres
Nature, 222, No 5198, p 1021 (June
1969) The Fulmer Research Institute has coated carbon fibre with thin tungsten films by vapour deposition. These may be used to reinforce metal matrices for use up to 1000°C. Main disadvantages are the high density of tungsten and its tendency to form brittle tungsten carbide during prolonged high temperature usage. There is also interest in aluminium coated fibres which could be used up to 400°C but would have neither of these drawbacks. (69/3/8)
SINGH, B. N., COTTERILL, P. and WALDRON, M. B.
The effect of dispersoid properties on the dispersion strengthening of carbonyl iron
Powder Metallurgy, 12, No 23, p 157
(1969) It was shown experimentally that the mechanical properties of dispersion strengthened Fe depend on the dispersoid particle shape as well as part i d e size and separation. Alloys were prepared b y sintering carbonyl Fe, containing different amounts of
62 COMPOSITES September 1969
Transactions AIME, 245, p 880 (1969) Copper whiskers of between 70 and 100 microns diameter and of different orientations were grown from CuI by reduction with H2 at 500°C and subjected to tensile testing at temperatures from 77 ° to 473°K. The temperature dependence of flow stress was similar to that of bulk single crystals. In general the results suggested a high grown-in dislocation density. (16 references) (69/3/10)
STOLARZ, VON ST, GOLONKA, J. and KURZEJA, J.
The technology of production of sintered single- and multi-layer contact bushes of W-Cu-Ni alloys
Planseeberichte fur Pulvermetallurgie, 17, p 10 (1969) Techniques were investigated for the production of contact bushes from W-Cu and W-Cu-Ni alloys using the infiltration method and/or liquid phase sintering. The effects of production conditions on the properties of the bushes were studied. As well as producing bushes of a single alloy, it was possible to prepare bushes consisting of layers of alloys of different composition. Methods of brazing the
latter to supports are described. (14 references) (69/3/11)
WILCOX, B. A. and CLAUER, A. H.
Tensile and creep deformation of a fiber reinforced Mg-Li alloy
Transactions AIME, 245, p 945 (1969) Reinforcement of a Mg-14wt% Lilwt% A1 alloy matrix with continuous wires of precipitation hardened stainless steel resulted in a significant increase in ultimate strength and strength-to-density ratio, from room temperature up to 200°C. The ultimate strength of the composite was lower than the value predicted by the law of mixtures. It was considered that this was due to some misalignment of the wires. The creep of the composite and of the free wires was logarithmic whereas the unreinforced matrix alloy exhibited steady state creep behaviour. It was concluded that the creep of the wires controlled the creep of the composite. A relationship existed between the creep rate, e, of the composite and the average tensile stress on the fibres, 5f, such that ~rv(of) 3 4. (12 references) (69/3/12)
Resin matrices ATKINSON, H. E.
Engineering basis for RP chemicalresistant tanks
Modern Plastics, 46, 6, p 108 (June 1969) Composite specimens of potential tank materials were made up from various combinations of E and C glass mat and roving in epoxy and polyester resin systems to meet the demands of tests under total immersion or one-side exposure conditions in hostile environments. The effects of chemical attack on mechanical properties, stress on chemical resistance and temperature on strength retention are reported and fabrication techniques relevant to good performance are reviewed. (69/4/1) BILBE, W. G.
Designing with PTFE
Engineering, Materials and Design, 12, No 6, p 871 (June 1969} A general review article on the uses of PTFEmentions a new product (Forma-