Mechanochemical effect on low temperature synthesis of AlN by direct nitridation method

A modified direct nitridation method for formation of nano-AlN whiskers

“…There are two primary commercial techniques reported for the production of AlN powders: the direct nitridation of aluminium or aluminium salts by nitrogen or ammonia [6][7][8][9][10][11][12] and the carbothermal reduction and nitridation of alumina [13][14][15][16]. The later one involves the reduction of Al 2 O 3 or Al(OH) 3 with carbon and simultaneous nitridation by nitrogen to AlN powder at temperatures around 1700-1900 • C [11].…”

“…Al 2 S 3 [8]) to lower the temperature of nitridation commencement, reacting in mixtures of nitrogen and ammonia gases instead of pure nitrogen gas [10], or incorporating some additives (e.g. Mg [6,7], Li-salts [11,12]) have been investigated in order to promote nitridation conversion.…”

Application of mechanochemical synthesis of advanced materials

“…Some non-oxide materials, such as ZrB 2 , WC, AlN, etc. are successfully obtained via mechanochemical reactions at argon or nitrogen atmosphere [15][16][17][18]. ZrB 2 were produced by by magnesiothermic reduction, reaction (1), via mechano-chemical process at argon atmosphere [16].…”

In Situ Fabrication of AlN Coating by Reactive Plasma Spraying of Al/AlN Powder

“…Generally, to promote the nitridation conversion in the direct nitriding method, various means of decreasing the nitriding commencement temperature have been investigated such as the nitridation of Al salts (e.g., Al 2 S 3 ) [19], using mixtures of nitrogen and ammonia gases instead of pure nitrogen gas [20] and incorporating certain additives (e.g., Mg [21,22], Li-salts [23,24]). Some other studies have mixed Al powder with a dispersion agent such as carbon black [25] or ammonium chloride (NH 4 Cl) [26,27] and then nitrided the mixture under high temperature conditions.…”