Making composite molding material precursor containing fine metallic matrix phase and reinforcing phase, extrudes molten metal powder and reinforcing matrix together

摘要

A first section of an extruder is supplied with the metallic matrix which is carried toward an outlet nozzle. Particles forming a reinforcing phase are supplied in a second region of the extruder. A mixture is formed from the reinforcing particles and the at least partially-molten metallic matrix phase. Before, during or after passing through the outlet nozzle, the mixture is cooled to a temperature below the solidus of the metallic matrix phase. The metallic matrix and/or reinforcing particles are supplied to the extruder under a protective gas atmosphere. The metallic matrix phase is supplied as solid metal particles. These comprise magnesium, zinc, aluminum or their alloys. The metal particles are granules of mean diameter 1 mu m to 10 mm. The reinforcing particles are made from metallic and/or non-metallic inorganic materials. The reinforcing particles comprise fibers and/or particles. The fibers are 3 - 20 mu m thick and their lengths are 5 nm to 10 mu m. Particle mean diameter is 10 nm to 100 mu m. The metal particles become at least partly-molten in the second section of the extruder, during transport to the outlet nozzle. The efflux from the nozzle is transferred into a mold in a flowing state. Once set, the mixture is granulated. Contact time between the at least part-molten metallic phase and the reinforcing phase is less than 20 minutes, preferably less than 15 minutes. The extruder has at least one, preferably two limbs. The extruder includes at least one mixer.