摘要:
This invention is directed to the fabrication of SiC fiber reinforced, ceramic matrix composite articles exhibiting superior high temperature oxidative stability, those articles comprising:(a) a glass-ceramic matrix wherein alkali metal and/or alkaline earth metal aluminosilicate crystals constitute the predominant crystal phase;(b) a fiber reinforcing phase comprising SiC fibers coated with an alkali metal and/or alkaline earth metal sheet silicate entrained within said glass-ceramic matrix; and(c) a borosilicate glass phase dispersed as an intergranular glass within said glass-ceramic matrix, said borosilicate glass phase generally being present in an amount sufficient to provide an intergranular glass phase therein.
摘要:
The invention relates to fiber reinforced composite materials, and a method for making, in which ceramic, glass-ceramic or glass matrix precursor particles are coated with a layer of sheet silicate crystals, or precursors for sheet silicate crystals, and then combined with a fiber reinforcement phase disposed within the matrix consisting of amorphous or crystalline inorganic fibers. The method results in a composite material in which a substantially continuous layer of sheet silicate is provided on the matrix particles, resulting in a substantially continuous sheet silicate interface between the inorganic fibers and the ceramic, glass or glass-ceramic matrix.
摘要:
Ceramic matrix composite articles comprising a ceramic, glass-ceramic or glass matrix and a fiber reinforcement phase disposed within the matrix consisting of amorphous or crystalline inorganic fibers, wherein there is provided, on or in close proximity to the surfaces of the inorganic fibers, a layer of sheet silicate crystals constituting a sheet silicate interface between the inorganic fibers and the ceramic, glass, or glass-ceramic matrix. Optionally, the composition of the matrix may be the same as the sheet silicate interface so that the matrix provides the sheet silicate layer.
摘要:
Ceramic matrix composite articles comprising a ceramic, glass-ceramic or glass matrix and a fiber reinforcement phase disposed within the matrix consisting of amorphous or cyrstalline inorganic fibers, wherein there is provided, on or in close proximity to the surfaces of the inorganic fibers, a layer of sheet silicate crystals constituting a sheet silicate interface between the inorganic fibers and the ceramic, glass, or glass-ceramic matrix. Optionally, the composition of the matrix may be the same as the sheet silicate interface so that the matrix provides the sheet silicate layer.
摘要:
Silicon nitride reinforcing fibers provided with a protective surface coating comprising a boron nitride base layer and, optionally, an alumina overcoating, and fiber-reinforced ceramic matrix composite products incorporating the protectively-coated fibers, are disclosed. The composites offer significantly improved high temperature strength in combination with low dielectric constant and low dielectric loss characteristics.
摘要:
This invention relates to the production of laminated structures consisting essentially of a light weight interior member prepared from a glass, glass-ceramic, or ceramic, an exterior member prepared from a glass, glass-ceramic, or ceramic, and a bonding member prepared from a glass, glass-ceramic, or ceramic. The light weight interior member may be composed of a porous body, a corrugated body, or a honeycomb body. In a preferred embodiment, at least one of said members is reinforced through the entrainment of ceramic fibers and/ or whiskers. In the most preferred embodiment, each exterior and interior member is reinforced through the entrainment of ceramic fibers and/or whiskers and the bonding member is reinforced through the entrainment of ceramic whiskers.
摘要:
The present invention is directed to the production of SiC whisker- and/or fiber-reinforced, internally-nucleated glass-ceramic matrix composite articles consisting essentially of 0.5-60% by weight SiC whiskers and/or 15-70% by volume ceramic fibers substantially uniformly distributed in a glass-ceramic matrix consisting essentially, in weight percent on the oxide basis, of 16-20%, CaO, 38.5-46% Al.sub.2 O.sub.3, 35-42% SiO.sub.2, and up to 10% total of at least one nucleating agent in the indicated proportion selected from the group consisting of 0.1-3% Cr.sub.2 O.sub.3, 0.25-3% HfO.sub.2, 2-5% MoO.sub.3, 0.25-3% Nb.sub.2 O.sub.5, 0.25-3% Ta.sub.2 O.sub.5, 0.25-3% WO.sub.3, and 1-10% ZrO.sub.2, wherein Al.sub.2 O.sub.3 is present in an amount which is at least 5 mole percent and up to 50 mole percent in excess of that present in stoichiometric triclinic anorthite, and wherein the predominant crystal phases in the glass-ceramic are triclinic anorthite and mullite and/or .alpha.-Al.sub.2 O.sub.3. Up to 1.5% As.sub.2 O.sub.3 may advantageously be included in the composition.
摘要:
There is disclosed a laminated ceramic structure including a facing member and a backing member, the two members being bonded together either directly or through an intermediate layer, the facing member being formed from a very hard ceramic such as a carbide having a KHN.sub.100 value in excess of 1000 kg/mm.sup.2, the backing member being a glass or glass-ceramic matrix having an enhanced capability or absorbing impact energy, preferably being fiber reinforced and having an energy absorbing capacity in excess of 10 KJ/m.sup.2.
摘要翻译:公开了一种层叠陶瓷结构,其包括面向构件和背衬构件,两个构件直接地或通过中间层结合在一起,面对构件由非常硬的陶瓷形成,例如具有超过KHN100值的碳化物 1000kg / mm2的背衬构件是具有增强的能力或吸收冲击能量的玻璃或玻璃 - 陶瓷基体,优选地是纤维增强并具有超过10KJ / m 2的能量吸收能力。
摘要:
The present invention is directed to SiC whisker and/or fiber reinforced glass-ceramic matrix composite articles wherein an alkaline earth aluminosilicate constitutes the predominant crystal phase. More particularly the composite articles will consist essentially of 10-60% by weight SiC whiskers and/or 15-70% by volume ceramic fibers and the glass-ceramic matrix will consist essentially, by weight on the oxide basis, of______________________________________ CaO 0-25 MgO 0-15 SrO 0-30 Na.sub.2 O 0-4 CaO + SrO 10-30 K.sub.2 O 0-6 Al.sub.2 O.sub.3 25-38 TiO.sub.2 0-12 SiO.sub.2 35-60 ZrO.sub.2 0-15 BaO 0-25 As.sub.2 O.sub.3 0-3 BaO + MgO + Na.sub.2 O + K.sub.2 O + TiO.sub.2 ZrO.sub.2 + As.sub.2 O.sub.3 0-30 ______________________________________ The preferred predominant crystal phase is selected from the group of anorthite and its pseudo-binaries, with mullite, cordierite, barium osumilite, and albite solid solution.
摘要:
The invention includes environmentally stable athermalized optical fiber gratings and methods of making such stabilized optical waveguide fiber grating. Stable humidity-resistant athermalized fiber Bragg gratings are provided by stabilizing a negative thermal expansion substrate and utilizing a durable frit to attach the fiber Bragg grating to the substrate.