Interface of an Al-(Al₂O₃)_p composite modified with nickel

A composite material with aluminium matrix and alumina particles coated with nickel was investigated. The nickel coating with thickness up to 1 μm formed by a chemical method consisted of a thin film directly on the alumina surface, porous zone of grains 100 nm size and discontinuous zone of grain agglomerates. As a result of the interaction between the alumina particles coated with nickel and the aluminium matrix, dissolution of nickel in aluminium occurred and reactive bonding took place. In the interface characterized by SEM and TEM methods nickel aluminide and locally nickel-iron aluminide were identified. The presence of complex aluminide was a result of local iron impurity in the aluminium powder.