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Densification of ceramic-metal composites
Abstracts of patents US patents abstracts are prepared by Dr R.J. Hand, University of Sheffield, UK
US P A T E N T S COMPONENTS Whisker-reinforced material
ceramic
cutting
tool
Brandt, N.G.L. (Sandvik AB, Sandviken, Sweden) US Pat 5 141 901 (25 August 1992) A ceramic cutting insert, for chipforming machining of steel, comprises an alumina matrix reinforced with less than 20% zirconia and 5 to 50 vol% of whiskers or platelets of a tantalum nitride, carbide and/or boride. The whiskers or platelets have a linear expansion coefficient between 300 and 1300 K which is at most 85% of that of alumina.
Mass loaded composite rotor for vibro-acoustic application Blake, W.K., Macander, A.B. and Gershfeld, J. (Secretary of the Navy, Washington, DC, USA) US Pat 5 145 320 (8 September 1992) The rotor has a hub with at least one blade extending from the hub. A portion of the blade is a multi-dimensionally braided fibre reinforcement which totally encompasses a rubber insert and has no planes of delamination. There is also a high density region which is located in the high vibration active regions of the blade, A resin matrix impregnates the fibre reinforcement and bonds the other regions of the blade together.
(Baker, R.T.K. and Rodriguez, N.M. of Opelika, AL, USA) US Pat 5 149 584 (22 September 1992) A high performance composite has carbon filaments grown from a primary structure of carbon fibres in a polymeric or carbon matrix. The primary structure is more than 75% crystalline and the filaments have branched, spiral or helical forms.
Thermoplastic composite plate material and products moulded from the same Kimoto, Y., Murata, K. and Muraki, T. (Toray Industries, Inc, Tokyo, Japan) US Pat 5 151 322 (29 September 1992) A thermoplastic composite is described, the mechanical properties of which in any two directions at 45 ° to each other are within + 10%. The plate is composed of a polyether imide resin and 30 to 50 vol% of strip pieces which are distributed randomly in planes parallel to the surface of the plate. The strips comprise unidirectional carbon, glass or polyaramid fibres and are between 5 and 30 mm long, 5 to 20 mm wide and are less than 0.1 mm thick.
Polymer composites based cellulose-Vl (Beshay, A.D. of Trois-Rivieres, Quebec, Canda) US Pat 5 153 241 (6 October 1992) A polymer or copolymer matrix is reinforced with cellulose fibres that have been grafted by a free radical generating process with a titanium coupling agent.
Composite orthopedic implant Dumbleton, J.H., Lin, R.Y., Stark, C.F. and Crippen, T.E. (Pfizer Hospital Products Group, Inc, New York, NY, USA) US Pat 5 181 930 (26 January 1993) An implant has an elongated core of thermoplastic embedded continuous fibres orientated along the longitudinal axis of the implant surrounded by a thermoplastic polymer which is moulded to the core. Around the filler there is a helically wound sheath of thermoplastic embedded fibres. The modulus of elasticity of the core is higher than that of the sheath, which in turn is higher than that of the filler.
MATERIALS Densification of ceramic-metal composites Pyzik, A.J., Snyder, I.G., McDonald, R.R. and Pecnenik, A. (The Dow Chemical Company, Midland, MI, USA) US Pat 5 143 540 (1 September 1992) A densified composition comprises at least 50 vol% ceramic and a metal. The ceramic may be one of or a mixture of SiB4, A1B2, A1,2C2, AI4BC, MgO, mullite, A1N and silicon nitride. The metal may be AI, Mg, Ti, Fe, Ni, Co, Mn, Cu, Si or their alloys.
Carbon fibre structures having improved interlaminar properties
Glass reinforced acetal polymer products Collins, G.L. and Ying, E, (Hoescht Celanese Corp, Somerville, N J, USA) US Pat 5 156 913 (20 October 1992) A composite comprises a normally crystalline acetal polymer and glass fibres or filaments. The fibres or filaments are sized with a normally non-crystalline elastomeric copolymer comprising (a) 15 to 45 tool% trioxane and 55 to 85 mol% of 1,3-dioxolane based on the total amount of trioxane and 1,3-dioxolane; and (b) 0.005 to 0.15 wt% of 1,4-butanediol diglycidyl ether or butadiene diepoxide based on the total weight of the copolymer.
Fibre reinforced ceramic matrix composites exhibiting improved high-temperature strength Chyung, K., Stempin, J.L. and Wexell, D.R. (Corning Inc, Corning, NY, USA) US Pat 5 164 341 (17 November 1992) An alkaline earth aluminosilicate glass-ceramic matrix is reinforced with boron-nitridecoated silicon carbide fibres. The matrix is selected from: (a) glass ceramics wherein the crystalline phase is triclinic anorthite and its pseudo-binaries with mullite, cordierite, barium osumilite, albite solid solution and gehlenite; or (b) internally nucleated glass ceramics wherein the crystalline phase is triclinic anorthite and at least one of mullite or :ealumina, with the alumina content being 10 to
001 0 - 4 3 6 1 / 9 4 / 1 0 / 0 9 5 9 - 0 2
50 mol% in excess of that of stoichiometric anorthite.
Cast composite material Skibo, M.D. and Schuster, D.M. (Dural Aluminium Composites Corp, San Diego, CA, USA) US Pat 5 167 920 (1 December 1992) A composite contains untreated and uncoated refractory particles with aspect ratios between 2 and 5 dispersed in a cast alloy matrix.
Silicon carbide-reinforced light alloy composite material Daimura, A., Ohta, T., Suzuki, T., lchikawa, M., Koshitani, H. and Fujishuro, H. (Honda Giken Kogyo Kabushiki Kaisha, Tokyo, Japan) US Pat 5 168 014 (1 December 1992) A lightweight alloy is reinforced with silicon carbide whiskers and spherical silicon carbide whisker aggregates which are less than 100 p_m in diameter. The silicon carbide whiskers contain between 0.05 and 5 wt% silica and 0.2 to 5 vol% of them are contained within the aggregates.
Fibre-reinforced composite toughened with porous resin particles Qureshi, S.P., Hoffman, R.E. and NewmanEvans, R.H. (Amoco Corporation, Chicago, IL, USA) US Pat 5 169 710 (8 December 1992) A composite with an epoxy resin matrix is reinforced with continuous carbon fibres and porous rigid polyamide particles with a mean diameter between 1 and 75/am.
Alumina short fibre reinforced magnesium alloy having stable oxide binders Hino, H., Komatsu, M., Shibita, K., Wadasako, M. and Ogawa, J. (Nissan Motor Company, Ltd, and Nichias Corp, both of Japan) US Pat 5 174 834 (29 December 1992) An alumina fibre-reinforced metal matrix of magnesium or magnesium alloy is described. The material is produced by infiltrating a preform of alumina short fibres which contains a binder of Li:O, CaO, a mixture of MgO and Li20, or a mixture of MgO and CaO.
Fibre-reinforced resin surface smoothness
composition
having
Shimaoka, G., Mizutani, M., Mio, 1. and Mimura, K. (Mitsubishi Gas Chemical Co, Inc, Tokyo, Japan) US Pat 5 179 152 (12 January 1993) The composition comprises 100 parts by weight of a thermoplastic resin, 5 to 1000 parts by weight of E-glass fibre sheet chips and 0 to 40 parts by weight of a thermoplastic elastomeric polymer. The resin comprises between 10 and 90 wt% aromatic polycarbonate resin and between 10 and 90 wt% of at least one of poly(ethylene terephthalate), poly(butylene terephthalate), poly(ethylene naphthalate) or poly(butylene naphthalate). The glass fibre chips are rectangular and have sides with lengths between 1 and 30 ram. The
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US P A T E N T S COMPONENTS Whisker-reinforced material
ceramic
cutting
tool
Brandt, N.G.L. (Sandvik AB, Sandviken, Sweden) US Pat 5 141 901 (25 August 1992) A ceramic cutting insert, for chipforming machining of steel, comprises an alumina matrix reinforced with less than 20% zirconia and 5 to 50 vol% of whiskers or platelets of a tantalum nitride, carbide and/or boride. The whiskers or platelets have a linear expansion coefficient between 300 and 1300 K which is at most 85% of that of alumina.
Mass loaded composite rotor for vibro-acoustic application Blake, W.K., Macander, A.B. and Gershfeld, J. (Secretary of the Navy, Washington, DC, USA) US Pat 5 145 320 (8 September 1992) The rotor has a hub with at least one blade extending from the hub. A portion of the blade is a multi-dimensionally braided fibre reinforcement which totally encompasses a rubber insert and has no planes of delamination. There is also a high density region which is located in the high vibration active regions of the blade, A resin matrix impregnates the fibre reinforcement and bonds the other regions of the blade together.
(Baker, R.T.K. and Rodriguez, N.M. of Opelika, AL, USA) US Pat 5 149 584 (22 September 1992) A high performance composite has carbon filaments grown from a primary structure of carbon fibres in a polymeric or carbon matrix. The primary structure is more than 75% crystalline and the filaments have branched, spiral or helical forms.
Thermoplastic composite plate material and products moulded from the same Kimoto, Y., Murata, K. and Muraki, T. (Toray Industries, Inc, Tokyo, Japan) US Pat 5 151 322 (29 September 1992) A thermoplastic composite is described, the mechanical properties of which in any two directions at 45 ° to each other are within + 10%. The plate is composed of a polyether imide resin and 30 to 50 vol% of strip pieces which are distributed randomly in planes parallel to the surface of the plate. The strips comprise unidirectional carbon, glass or polyaramid fibres and are between 5 and 30 mm long, 5 to 20 mm wide and are less than 0.1 mm thick.
Polymer composites based cellulose-Vl (Beshay, A.D. of Trois-Rivieres, Quebec, Canda) US Pat 5 153 241 (6 October 1992) A polymer or copolymer matrix is reinforced with cellulose fibres that have been grafted by a free radical generating process with a titanium coupling agent.
Composite orthopedic implant Dumbleton, J.H., Lin, R.Y., Stark, C.F. and Crippen, T.E. (Pfizer Hospital Products Group, Inc, New York, NY, USA) US Pat 5 181 930 (26 January 1993) An implant has an elongated core of thermoplastic embedded continuous fibres orientated along the longitudinal axis of the implant surrounded by a thermoplastic polymer which is moulded to the core. Around the filler there is a helically wound sheath of thermoplastic embedded fibres. The modulus of elasticity of the core is higher than that of the sheath, which in turn is higher than that of the filler.
MATERIALS Densification of ceramic-metal composites Pyzik, A.J., Snyder, I.G., McDonald, R.R. and Pecnenik, A. (The Dow Chemical Company, Midland, MI, USA) US Pat 5 143 540 (1 September 1992) A densified composition comprises at least 50 vol% ceramic and a metal. The ceramic may be one of or a mixture of SiB4, A1B2, A1,2C2, AI4BC, MgO, mullite, A1N and silicon nitride. The metal may be AI, Mg, Ti, Fe, Ni, Co, Mn, Cu, Si or their alloys.
Carbon fibre structures having improved interlaminar properties
Glass reinforced acetal polymer products Collins, G.L. and Ying, E, (Hoescht Celanese Corp, Somerville, N J, USA) US Pat 5 156 913 (20 October 1992) A composite comprises a normally crystalline acetal polymer and glass fibres or filaments. The fibres or filaments are sized with a normally non-crystalline elastomeric copolymer comprising (a) 15 to 45 tool% trioxane and 55 to 85 mol% of 1,3-dioxolane based on the total amount of trioxane and 1,3-dioxolane; and (b) 0.005 to 0.15 wt% of 1,4-butanediol diglycidyl ether or butadiene diepoxide based on the total weight of the copolymer.
Fibre reinforced ceramic matrix composites exhibiting improved high-temperature strength Chyung, K., Stempin, J.L. and Wexell, D.R. (Corning Inc, Corning, NY, USA) US Pat 5 164 341 (17 November 1992) An alkaline earth aluminosilicate glass-ceramic matrix is reinforced with boron-nitridecoated silicon carbide fibres. The matrix is selected from: (a) glass ceramics wherein the crystalline phase is triclinic anorthite and its pseudo-binaries with mullite, cordierite, barium osumilite, albite solid solution and gehlenite; or (b) internally nucleated glass ceramics wherein the crystalline phase is triclinic anorthite and at least one of mullite or :ealumina, with the alumina content being 10 to
001 0 - 4 3 6 1 / 9 4 / 1 0 / 0 9 5 9 - 0 2
50 mol% in excess of that of stoichiometric anorthite.
Cast composite material Skibo, M.D. and Schuster, D.M. (Dural Aluminium Composites Corp, San Diego, CA, USA) US Pat 5 167 920 (1 December 1992) A composite contains untreated and uncoated refractory particles with aspect ratios between 2 and 5 dispersed in a cast alloy matrix.
Silicon carbide-reinforced light alloy composite material Daimura, A., Ohta, T., Suzuki, T., lchikawa, M., Koshitani, H. and Fujishuro, H. (Honda Giken Kogyo Kabushiki Kaisha, Tokyo, Japan) US Pat 5 168 014 (1 December 1992) A lightweight alloy is reinforced with silicon carbide whiskers and spherical silicon carbide whisker aggregates which are less than 100 p_m in diameter. The silicon carbide whiskers contain between 0.05 and 5 wt% silica and 0.2 to 5 vol% of them are contained within the aggregates.
Fibre-reinforced composite toughened with porous resin particles Qureshi, S.P., Hoffman, R.E. and NewmanEvans, R.H. (Amoco Corporation, Chicago, IL, USA) US Pat 5 169 710 (8 December 1992) A composite with an epoxy resin matrix is reinforced with continuous carbon fibres and porous rigid polyamide particles with a mean diameter between 1 and 75/am.
Alumina short fibre reinforced magnesium alloy having stable oxide binders Hino, H., Komatsu, M., Shibita, K., Wadasako, M. and Ogawa, J. (Nissan Motor Company, Ltd, and Nichias Corp, both of Japan) US Pat 5 174 834 (29 December 1992) An alumina fibre-reinforced metal matrix of magnesium or magnesium alloy is described. The material is produced by infiltrating a preform of alumina short fibres which contains a binder of Li:O, CaO, a mixture of MgO and Li20, or a mixture of MgO and CaO.
Fibre-reinforced resin surface smoothness
composition
having
Shimaoka, G., Mizutani, M., Mio, 1. and Mimura, K. (Mitsubishi Gas Chemical Co, Inc, Tokyo, Japan) US Pat 5 179 152 (12 January 1993) The composition comprises 100 parts by weight of a thermoplastic resin, 5 to 1000 parts by weight of E-glass fibre sheet chips and 0 to 40 parts by weight of a thermoplastic elastomeric polymer. The resin comprises between 10 and 90 wt% aromatic polycarbonate resin and between 10 and 90 wt% of at least one of poly(ethylene terephthalate), poly(butylene terephthalate), poly(ethylene naphthalate) or poly(butylene naphthalate). The glass fibre chips are rectangular and have sides with lengths between 1 and 30 ram. The
@ 1 9 9 4 B u t t e r w o r t h - H e i n e m a n n Ltd C O M P O S I T E S . V O L U M E 25 . N U M B E R 9 . 1 9 9 4
959