摘要 |
The present invention comprises a process of preparing metal matrix composites which are reinforced by ceramic or graphite fibers, wherein the fibers are pretreated; first by a nickel coating, then by a second coating which is sacrificed when the fibers are ultimately immersed in a liquid metallic bath which becomes the matrix of the composite material formed. Usually the second coating is copper. In addition, a third coating on the fibers comprising a noble metal such as silver may also be used for certain matrix metal materials. Preferably the thickness of the nickel coating is a minimum of 0.5 micrometers and the second sacrificial coating is a minimum of 0.5 micrometers. After the fibers have been coated with the two or more successive coatings, they are incorporated into a metal matrix composite material by immersion in a molten bath of the desired matrix metal, or by placing the fibers in a suitable mold and casting the molten metal matrix around them, or by other suitable means. This may be done under ordinary atmospheric conditions without the use of vacuum or a protective atmosphere. |