| 摘要 |
<p>Disclosed are methods and materials for preparing investment molds useful in pressure infiltration casting of near net-shape metal or metal matrix composite (MMC) components. One embodiment of the invention includes disposing a slurry (30) of an appropriately sized refractory material and a vehicle around a preform (10) or fugitive pattern, removing the bulk of the vehicle, then curing/drying the refractory material to create an investment mold of the invention. Subsequently, pressure infiltration casting with a molten infiltrant (52) using the investment mold (44') permits infiltration of the mold cavity and/or preform without infiltration of the investment mold (44'). As a result, the investment mold readily is removed to provide the near net-shape metal or MMC component. In other embodiments of the invention, a non-fugitive pattern is used, typically with a modified refractory cement of the invention. In these embodiments, the non-fugitive pattern is removed after formation of the investment mold to provide a suitable mold cavity which may be used to produce near net-shape metal or MMC components.</p> |
