Fabrication of Al₂O₃‐Cu Nanocomposites Using Rotary Chemical Vapor Deposition and Spark Plasma Sintering

A two‐step rotary chemical vapor deposition technique was developed to uniformly mix Cu nanoparticles with the γ Al 2 O 3 powders, and then the as‐obtained powders were consolidated to Al 2 O 3 ‐Cu nanocomposites by spark plasma sintering. In the RCVD process, the metal‐organic precursor of copper dipivaloylmethanate (Cu(DPM) 2 ) reacted with O 2 and then was reduced by H 2 in order to erase the contamination of carbon. At 1473 K, the relative density of Al 2 O 3 ‐Cu increased with increasing C Cu and the maximum value was 97.7% at C Cu = 5.2 mass%. The maximum fracture toughness of Al 2 O 3 ‐Cu was 4.1 MPa m 1/2 at C Cu = 3.8 mass%, and 1 MPa m 1/2 higher than that of monolithic Al 2 O 3 , validating the beneficial effects of Cu nanoparticles.