摘要:
The present invention relates to the formation of whisker reinforced metal matrix composites in which complex boride or carbide whiskers having an aspect ratio of greater than 10:1 are distributed throughout a metal, metal alloy, or intermetallic matrix. Exemplary complex boride whiskers include TiNbB, TiTaB, TiVB, NbHfB, and TiNbMoB. Exemplary complex carbide whiskers include TiNbC, TiVC, TiZrC, TiHfC, and TiTaC. A method for the in-situ formation of complex boride and complex carbide whiskers within metallic matrices is disclosed which involves reacting a mixture of individual complex ceramic-forming constituents in the presence of a metal to precipitate the desired complex ceramic whiskers in a metal matrix.
摘要:
A method is taught for the in-situ precipitation of second phase materials, such as ceramic or intermetallic particles, in a metallic matrix. By means of the Direct Addition Process, metal-second phase composites having highly superior properties may be obtained. Compacts of second phase-forming constituents and solvent metal are directly added to a molten metal bath to precipitate the second phase in-situ. Exemplary materials include titanium diboride or titanium carbide in an aluminum matrix.
摘要:
A method is taught for the introduction of in-situ precipitated second phase materials, such as ceramic or intermetallic particles in a metal matrix, to a host metal. When an initial solvent-assisted reaction is utilized, metal-second phase composites having highly superior properties may be obtained. The invention may utilize the reaction of the second phase-forming constituents in a solvent metal medium to provide an intermediate material of finely-dispersed second phase particles in an intermediate metal matrix, in the form of a porous mass or sponge. Any desired loading of second phase in the final composite may be achieved by the admixture of this preformed intermediate material having a relatively high content of particulate material, with a molten host metal. Exemplary materials include titanium diboride in an aluminum matrix and titanium carbide in an aluminum matrix.
摘要:
This invention relates to a composite material comprising an in-situ precipitated second phase in an intermetallic matrix, and to the process for making such a composite.
摘要:
This invention relates to ceramic-ceramic composites comprising a dispersion of ceramic particles in a ceramic matrix. The production of these composites involves the in-situ precipitation of ceramic particles in a solvent metal matrix and the conversion of the matrix to a ceramic by reacting it with a matrix reactive species. Exemplary ceramic dispersoids include TiB.sub.2, ZrB.sub.2, TiC and TiN. Exemplary ceramic matrices include AlN, Al.sub.2 O.sub.3 and SiO.sub.2.
摘要:
This invention relates to a composite material comprising an in-situ precipitated second phase in an intermetallic matrix, and to the process for making such a composite.
摘要:
A method for welding metal composite materials, including metal-ceramic composites, whereby a weld or filler material is prepared by the in-situ precipitation of ceramic in a metallic matrix. The filler material may comprise boride, carbide, oxide, nitride, silicide, etc., while the matrix metal may constitute a alloy or intermetallic of two or more metals. A strong bond is achieved when welding two conventional metals, a conventional metal and a metal-ceramic composite, or two metal-ceramic composites.
摘要:
A method is taught for the in-situ precipitation of second phase materials, such as ceramic or intermetallic particles, in a substantial volume fraction of solvent metal matrix. The invention involves the propagating reaction of the second phase-forming constituents in a solvent metal medium to provide a porous composite of finely-dispersed second phase particles in the metal matrix. Exemplary materials include titanium carbide or titanium diboride in an aluminum matrix.
摘要:
A method is taught for the formation of intermetallic-second phase composite materials. The method involves the formation of a first metal-second phase composite comprising a relatively high loading of discrete, second phase particles distributed throughout a metal matrix, dilution of the first composite into an additional amount of metal to form a second composite comprising a lower loading of second phase particles within an intermediate metal matrix, and introduction of the second composite into another metal which is reactive with the intermediate metal matrix of the composite to form an intermetallic. A final intermetallic-second phase composite is thereby formed comprising a dispersion of discrete second phase particles throughout a final intermetallic matrix. The final intermetallic matrix may comprise a wide variety of intermetallic materials, with particular emphasis drawn to the aluminides and silicides. Exemplary intermetallics include Ti.sub.3 Al, TiAl, TiAl.sub.3, Ni.sub.3 Al, NiAl, Nb.sub.3 Al, NbAl.sub.3, Co.sub.3 Al, Zr.sub.3 Al, Fe.sub.3 Al, Ta.sub.2 Al, TaAl.sub.3, Ti.sub.5 Si.sub.3, Nb.sub.5 Si.sub.3, Cr.sub.3 Si, CoSi.sub.2 and Cr.sub.2 Nb. The second phase particulate materials may comprise ceramics, such as a borides, carbides, nitrides, oxides, silicides or sulfides, or may comprise an intermetallic other than the matrix intermetallic. Exemplary second phase particulates include TiB.sub.2, ZrB.sub.2, HfB.sub.2, VB.sub.2, NbB.sub.2, TaB.sub.2, MoB.sub.2, TiC, ZrC, HfC, VC, NbC, TaC, WC, TiN, Ti.sub.5 Si.sub.3, Nb.sub.5 Si.sub.3, ZrSi.sub.2, MoSi.sub.2, and MoS.sub.2.
摘要:
A method is taught for the introduction of in-situ precipitated second phase materials, such as ceramic or intermetallic particles in a metal matrix, to a host metal. When an initial solvent-assisted reaction is utilized, metal-second phase composites having highly superior properties may be obtained. The invention may utilize the reaction of the second phase-forming constituents in a solvent metal medium to provide an intermediate material of finely-dispersed second phase particles in an intermediate metal matrix, in the form of a porous mass or sponge. Any desired loading of second phase in the final composite may be achieved by the admixture of this preformed intermediate material having a relatively high content of particulate material, with a molten host metal. Exemplary materials include titanium diboride in an aluminum matrix and titanium carbide in an aluminum matrix.