Fabrication Of NiAl–Al2O3 Nanocomposite By Mechanical Alloying For ICNN 2008

Particulate composites are produced by adding reinforcement particles to the matrix. In the case of nanocomposites, however, uniform dispersion of the reinforcement particles throughout the matrix is a challenging task. Recently, ultrasonic stirring, high-energy mechanical milling and internal oxidation have been used to overcome the problem, i.e. distributing nanoscaled particles throughout the matrix [1].Mechanochemical synthesis involves mechanical activation of solid state displacement reactions in a ball mill. Thus, mechanical energy is used to induce chemical reactions. The chemical precursors typically consist of mixtures of oxides, chlorides and/or metals that react either during milling or during subsequent heat treatment to form a composite powder consisting of the dispersion of ultrafine particles within a matrix [2, 3].An earlier study demonstrated the Synthesis of Nanocrystalline NiAl by Mechanical Alloying of Ni and Al Powder Mixtures [4]. In this work NiAl–Al2O3 Nanocomposite was synthesized by mechanical alloying. The phase transformation occurring in MA process was investigated