| 摘要 |
An apparatus for bonding a particle material to near theoretical density, includes a chamber, a punch and die assembly for supporting a particle material, plungers for applying shear and/or axial pressures, and a power supply for applying a current. In the first stage, a pulsed current of about 1 to 20,000 amps., is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a shear force of about 5-50 MPa is applied. In the second stage, an axial pressure of about less than 1 to 2,000 MPa is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a steady current of about 1 to 20,000 amps. is applied. The apparatus may be used to bond metallic, ceramic, intermetallic and composite materials to near-net shape, directly from precursors or elemental particle material without the need for synthesizing the material. The method may also be applied to perform combustion synthesis of a reactive material, followed by consolidation or joining to near-net shaped articles or parts. The apparatus may further be used to repair a damaged or worn substrate or part, coat a particle onto a substrate, and grow single crystals of a particle material.
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