Hot pressing of Ni-Al2O3/Cu-Al2O3 cermet nanopowder

Al2O3 nanopowder chemically coated with Ni and Cu was hot-pressed. The influences of Ni/Cu contents on densification, microstructure and properties were studied. Proper content of Ni/Cu coated on the Al2O3 nanopowder can enhance densification effectively, and thus sintered temperature is decreased. The metal phase as a second phase can greatly decrease Al2O3 grain size, but hardness and strength are decreased too. The decrease of hardness is due to the effect of soft metal phase of Ni/Cu. The decrease of strength is attributed to the weak bonding force of Ni/Cu to Al2O3 powders.