CONTINUOUS-HEATING IGNITION TESTING OF HYBRID Al-Ni-CuO REACTIVE COMPOSITES FABRICATED BY ULTRASONIC POWDER CONSOLIDATION

摘要

Powder-based fabrication of hybrid reactive composites combining bimetallic and thermite endothermic reactions requires a consolidation process that produces dense composites with no reactions among the constituents. Reactive composites 2Al-3CuO-x(Al-Ni) (x =1 - 4) were fabricated from nano-thick Al and Ni flakes and CuO nanoparticles by ultrasonic powder consolidation and tested for their ignition characteristics in continuous heating. The hybrid bimetallic thermite composites with x ≥ 2 ignited well below the melting point of aluminum, while maintaining large heat outputs. Combining the large heat output of the Al-metal oxide thermite reaction and the low ignition temperature of Al-Ni exothermic reactions in single reactive composites, the hybrid bimetallic-thermite composites are suited for controlled local heating, as in micro-joining, where small, easy-to-ignite, high-output heat sources are required.