Abstract:
The present invention relates to a novel process for forming thin metal matrix composite bodies. Particularly, an infiltration enhancer and/or an infiltrating atmosphere are in communication with a filler material or preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material or preform. Such spontaneous infiltration occurs without the application of any pressure or vacuum. In an embodiment of the present invention, the filler material may be sprayed upon a thin sheet of matrix metal. Alternatively, the filler material may be shaped via tape casing, slip casting, etc. to provide a thin preform. In another embodiment of the present invention, a body of matrix metal may be coated with a filler material such that upon spontaneous infiltration a metal matrix composite body is produced which inversely replicates the configuration of the original body of matrix metal.
Abstract:
The compositions of this invention comprise uncrosslinked reaction mixtures comprising (1) at least one organic monomer, oligomer or polymer comprising a multiplicity of organic, electrophilic substituents, and (2) at least one metal-containing polymer comprising a metal-nitrogen polymer. Preferred compositions of this invention comprise reaction mixtures comprising (1) at least one organic monomer, oligomer or polymer comprising a multiplicity of organic, electrophilic substituents, and (2) at least one of: silicon-nitrogen polymers, aluminum-nitrogen polymers and boron-nitrogen and polymer combinations thereof comprising a multiplicity of sequentially bonded repeat units the compositions comprising the reaction products of the reaction mixtures, and the compositions obtained by crosslinking the reaction products of the reaction mixtures. The crosslinking may be effected through at least one of thermal-based, radiation-based, free radical-based or ionic-based crosslinking mechanisms. Furthermore, the reaction mixtures, the composition comprising the reaction products and the crosslinked composition may further comprise at least one filler or reinforcement. The composition may be molded or shaped by various techniques into numerous useful articles. Furthermore, the compositions may be applied as coatings by various techniques onto numerous articles to enhance the articles' usefulness.
Abstract:
The present invention relates to the use of a gating means (3) in combination with a spontaneous infiltration process to produce a metal matrix composite body. Particularly, a permeable mass of filler material or a preform (2) is spontaneously infiltrated by molten matrix metal (5) to form a metal matrix composite body. A gating means (3) is provided which controls or limits the areal contact between molten matrix metal (5) and the filler material or preform (2). The use of a gating means (3) provides for control of the amount of matrix metal (5) which can contact the preform (2) or filler material, which may result in less machining of a formed metal matrix composite body compared with a similar metal matrix composite body made without a gating means (3). Moreover, the use of a gating means (3) ameliorates the tendency of a formed metal matrix composite body to warp due to the contact between the formed composite body and matrix metal carcass.