Abstract:
The present invention relates to novel methods for shaping a filler material into a porous preform and subsequently filling at least a portion of the porous preform with a second material to form a composite body. Specific aspects of the invention include novel combinations of materials to form the preform in combination with novel processing techniques for shaping the combinations of materials into a porous preform.
Abstract:
This invention relates generally to a novel method for removing metal from a formed self-supporting body. A self-supporting body is made by reactively infiltrating a molten parent metal into a bed or mass containing a boron donor material and a carbon donor material (e.g., boron carbide) and/or a boron donor material and a nitrogen donor material (e.g., boron nitride) and, optionally, one or more inert fillers. Once the self-supporting body is formed, it is then subjected to appropriate conditions which causes metallic constituent contained in the self-supporting body to be at least partially removed.
Abstract:
This invention relates generally to novel methods of preparing self-supporting bodies and to the novel products made thereby. In its more specific aspects, this invention relates to methods of producing self-supporting bodies having controlled porosity and graded properties and comprising one or more boron-containing compounds, e.g., a boride or a boride and a carbide. The method comprises, in one embodiment, reacting a powdered parent metal, in molten form, with a bed or mass comprising a boron donor material and a carbon donor material (e.g., boron carbide) and, optionally, one or more inert fillers, to form the body. In another embodiment, both of a powdered parent metal and a body or pool of molten parent metal are induced to react with a bed or mass comprising a boron donor material and a carbon donor material (e.g., boron carbide) and, optionally, one or more inert fillers to produce a grading effect in the resultant body. In addition, combustible additives (e.g., gelatin, corn starch, wax, etc.) can be mixed with the bed or mass comprising, for example, a boron carbide material to aid in porosity production and control. When the self-supporting body of the instant invention is formed while in contact with a previously formed ceramic, metal or composite body, a bond can be formed between the two bodies, thus creating a macrocomposite body.
Abstract:
A reaction injection molding process for preparing ceramics having at least two compositionally distinct ceramic phases is disclosed. For example, block copolymers prepared from an aluminum-nitrogen polymer and a polysilazane are filled with a ceramic powder, a metal powder or mixtures thereof and cured in the mold. An AlN/SiC-containing ceramic is formed by pyrolysis of the molded articles in a nonoxidizing atmosphere.
Abstract:
The present invention relates to modifying the properties of a metal matrix composite body by a post formation process treatment and/or a substantially contiguous modification treatment. The post formation process treatment may be applicable to a variety of metal matrix composite bodies produced by various techniques, and is particularly applicable to modifying the properties of a metal matrix composite body produced by a spontaneous infiltration technique. The substantially contiguous modification process may also be used primarily in conjunction with metal matrix composite bodies produced according to a spontaneous infiltration technique. Particularly, at least a portion of the matrix metal of the metal matrix composite body and/or the filler material of the metal matrix composite body is modified or altered during and/or after the formation process.
Abstract:
The present invention relates to a novel process for removal of at least a portion of at least one metallic component of a metallic constituent from a multi-phase composite body. Particularly, by providing at least one of an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere to be in communication with a permeable mass, which contacts at least a portion of a composite body, said metallic component of the composite body, when made molten, is caused to spontaneously infiltrate the permeable mass. Such spontaneous infiltration occurs without the requirement for the application of any pressure or vacuum.
Abstract:
The invention relates to novel wear and corrosion resistant parts for use in liquids and/or solids transportation and, in a particularly preferred embodiment, the invention relates to slurry pump parts, and methods for making the same. More specifically, the present invention relates to a novel means for joining together at least two parts, and the bodies formed thereby, for use in liquids and/or solids transportation and even more specifically to a novel means for forming a slurry pump suction side liner comprising joining a suction side wear plate to a substrate material or backing plate, which combination of materials may be used in a slurry pump.
Abstract:
There is disclosed a method for producing a self-supporting ceramic body by oxidation of a molten precursor metal with a vapor-phase oxidant to form an oxidation reaction product and inducing a molten flux comprising said molten precursor metal through said oxidation reaction product. A second metal is incorporated into said molten flux during the oxidation reaction. The resulting ceramic body includes sufficient second metal such that one or more properties of said ceramic body are at least partially affected by the presence and properties of said second metal in the metallic constituent.
Abstract:
This invention relates generally to a novel method of manufacturing a composite body. More particularly, the present invention relates to a method for modifying the resultant properties of a composite body, by, for example, minimizing the amount of porosity present in the composite body. Moreover, additives, whether used alone or in combination, (1) can be admixed with the permeable mass, (2) can be mixed or alloyed with the parent metal, (3) can be placed at an interface between the parent metal and the preform or mass of filler material, (4) or any combination of the aforementioned methods, to modify properties of the resultant composite body. Particularly, additives such as VC, NbC, WC, W2B5, TaC, ZrC, ZrB2, SiB6, SiC, MgO, Al2O3, ZrO2, CeO2, Y2O3, La2O3, MgAl2O4, HfO2, ZrSiO4, Yb2O3 and Mo2B5 can be combined with the permeable mass in an amount of about 5-50 percent by weight, prior to reactively infiltrating the permeable mass. Moreover, an additive may also include substantially pure elemental metals (e.g., Nb, Ti, Hf, V, Ta, Cr, Mo, Al, Cr, Si, Co and W) which may be provided by any of the methods discussed above herein.