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Process for producing reinforced cementitious compositions and the products produced thereby
feldspar as a minor phase on thermal crystallization; (3) glasses which yield anorthite and/ or cordierite as the principal phase and potash feldspar as a minor phase on thermal crystallizaton; and (4) glasses which yield anorthite as the principal phase and optionally containing 0-15 weight% of particulate zirconia. In all cases the frit has a thermal curing range of at least 150"C between the its flow temperature and crystallization temperature, and the flits are curable to a crystalline seal at a temperature not exceeding 1500"C.
Cold-moulded cementitious composites reinforced with surface-modified polyamide fibres and method of preparing same Holden, D.A. and Dimitry, S. (Relmech Manufacturing Limited, Elmira, Canada) US Pat 4974522 (4 December 1990,) Surface treatment of polyamide fibres is effected with an alkaline hydroxide or alkoxide solution. This improves bonding of the fibres to the inorganic cementitious matrix into which they are to be incorporated. Process for producing high strength carboncarbon composite Takabatake, M. (Petoca Ltd, Tokyoto, Japan) US Pat 4975261 (4 December 1990) An aggregate of carbon fibre is impregnated with a liquid dispersion of either a carbonaceous fine powder with an average particle size of 0.07-12 }tin or a carbonaceous short fibre cut or ground to a fibre length < 2 mm, to
form a reinforcement material containing about 22% fine powder or short fibre. This reinforcement material is impregnated with one or more of thermosetting phenolic resin, furan resin or a pitch and the whole is carbonized to form a carbon/carbon composite.
Surface-coated SiC whiskers, processes for preparing the same, ceramic reinforced with the same, and process for preparing said reinforced ceramic Sugihara, K., Yamamoto, M., Kida, T. and Fukazawa, M. (Tokai Carbon, Tokyo, Japan) US Pat 4975302 (4 December 1990) SiC whiskers are dispered in a solution of an organosilicon polymer in an organic solvent, separated by filtration and dried. The coated whiskers are heated in a nitriding atmosphere to a temperature of 1200-1600"C to form Si3N4 layers on the surfaces of the whiskers. Process for producing reinforced cementitious compositions and the products produced thereby Thiery, J. (Vetrotex Saint-Gobain, Chambery, France) US Pat 4975396 (4 December 1990) A polymer is mixed with sufficient water to maintain a subsequently added cementitious composition in an aqueous phase until it is cured. At least one metakaolin additive, followed by a sufficient amount of silica sand and a cement to form a homogeneous thixotropic paste, are mixed with the first mixture. Alkaline-resistant glass fibres are mixed with
the resultant paste to produce a reinforced cementitious composition.
Method for making ceramic matrix composite article Allaire, R.A. (Corning, Incorporated, Coming, NY, USA) US Pat 4976761 (11 December 1990) Glass powder is adhered to one or more continuous strands of inorganic fibrous reinforcement which is then heated in a hot zone to a temperature which is at least above the annealing temperature of the glass. Whilst it is hot it is simultaneously collected and consolidated on a rotating collection mandrel to form a dense composite winding. The consolidation results solely from the tension applied to the strand in the opposite direction to the direction of collection of the strand. Process for the production of a composite material with matrix and reinforcing fibres of carbon (Rousseau, G. and Pastureau, N. of Saint Aubain de Medoc and Eysines, respectively, France) US Pat 4976899 ( l l December 1990) A deformable substrate of carbon fibres, each of which is coated with a fine silicon carbide coating deposited by chemical vapour deposition, is shaped and densified to form a carbon matrix containing at most 20 weight% of finely divided silicon carbide. The outer surface of the matrix is covered with cracked silicon carbide and these cracks are filled with a borosilicate glass.
COMPOSITES. NOVEMBER 1992
469
Cold-moulded cementitious composites reinforced with surface-modified polyamide fibres and method of preparing same Holden, D.A. and Dimitry, S. (Relmech Manufacturing Limited, Elmira, Canada) US Pat 4974522 (4 December 1990,) Surface treatment of polyamide fibres is effected with an alkaline hydroxide or alkoxide solution. This improves bonding of the fibres to the inorganic cementitious matrix into which they are to be incorporated. Process for producing high strength carboncarbon composite Takabatake, M. (Petoca Ltd, Tokyoto, Japan) US Pat 4975261 (4 December 1990) An aggregate of carbon fibre is impregnated with a liquid dispersion of either a carbonaceous fine powder with an average particle size of 0.07-12 }tin or a carbonaceous short fibre cut or ground to a fibre length < 2 mm, to
form a reinforcement material containing about 22% fine powder or short fibre. This reinforcement material is impregnated with one or more of thermosetting phenolic resin, furan resin or a pitch and the whole is carbonized to form a carbon/carbon composite.
Surface-coated SiC whiskers, processes for preparing the same, ceramic reinforced with the same, and process for preparing said reinforced ceramic Sugihara, K., Yamamoto, M., Kida, T. and Fukazawa, M. (Tokai Carbon, Tokyo, Japan) US Pat 4975302 (4 December 1990) SiC whiskers are dispered in a solution of an organosilicon polymer in an organic solvent, separated by filtration and dried. The coated whiskers are heated in a nitriding atmosphere to a temperature of 1200-1600"C to form Si3N4 layers on the surfaces of the whiskers. Process for producing reinforced cementitious compositions and the products produced thereby Thiery, J. (Vetrotex Saint-Gobain, Chambery, France) US Pat 4975396 (4 December 1990) A polymer is mixed with sufficient water to maintain a subsequently added cementitious composition in an aqueous phase until it is cured. At least one metakaolin additive, followed by a sufficient amount of silica sand and a cement to form a homogeneous thixotropic paste, are mixed with the first mixture. Alkaline-resistant glass fibres are mixed with
the resultant paste to produce a reinforced cementitious composition.
Method for making ceramic matrix composite article Allaire, R.A. (Corning, Incorporated, Coming, NY, USA) US Pat 4976761 (11 December 1990) Glass powder is adhered to one or more continuous strands of inorganic fibrous reinforcement which is then heated in a hot zone to a temperature which is at least above the annealing temperature of the glass. Whilst it is hot it is simultaneously collected and consolidated on a rotating collection mandrel to form a dense composite winding. The consolidation results solely from the tension applied to the strand in the opposite direction to the direction of collection of the strand. Process for the production of a composite material with matrix and reinforcing fibres of carbon (Rousseau, G. and Pastureau, N. of Saint Aubain de Medoc and Eysines, respectively, France) US Pat 4976899 ( l l December 1990) A deformable substrate of carbon fibres, each of which is coated with a fine silicon carbide coating deposited by chemical vapour deposition, is shaped and densified to form a carbon matrix containing at most 20 weight% of finely divided silicon carbide. The outer surface of the matrix is covered with cracked silicon carbide and these cracks are filled with a borosilicate glass.
COMPOSITES. NOVEMBER 1992
469