Nickel-aluminide synthesis

The initial studies on nickel-aluminide synthesis defined a number of important issues in shock-induced solid state synthesis. This work was extended to the influence of powder particle morphology in recent work of Thadhani and... 

Intermetallics also represent an ideal system for study of shock-induced solid state chemical synthesis processes. The materials are technologically important such that a large body of literature on their properties is available. Aluminides are a well known class of intermetallics, and nickel aluminides are of particular interest. Reactants of nickel and aluminum give a mixture with powders of significantly different shock impedances, which should lead to large differential particle velocities at constant pressure. Such localized motion should act to mix the reactants. The mixture also involves a low shock viscosity, deformable material, aluminum, with a harder, high shock viscosity material, nickel, which will not flow as well as the aluminum. 

Combustion synthesis of nickel aluminides in the VCS mode was first demonstrated during sintering of a Ni-Al mixture (Naiborodenko et al, 1968). Shortly thereafter, the SHS mode of combustion synthesis was reported for a variety of aluminides, including those of Ni, Zr, Ti, Cr, Co, Mo, and Cu (Naiborodenko et al, 1970, 1982 Naiborodenko and Itin, 1975a,b Maslov et al, 1976, 1979 Itin et al, 1980). 

Rabin, B. H., Bose, A., and German, R. M., Combustion synthesis of nickel aluminides. In Combustion and Plasma Synthesis of High-Temperamre Materials (Z. A. Munir and J. B. Holt, eds.). VCH PubUshers, New York, 1990, p. 114. 

Rogachev, A. S., Khomenko, I. O., Varma, A., Merzhanov, A. G., and Ponomarev, V. I., The mechanism of self-propagating high-temperature synthesis of nickel aluminides. Part II Crystal structure formation in a combustion wave. Int. J. SHS, 3,239 (1994a). 

Wenning, L. A., Lebrat, J.-P, and Varma, A, Some observations on unstable self-propagating high-temperature synthesis of nickel aluminides. J. Mater. Syn. Proc., 2, 125 (1994). 

K. A. Philpot and Z. A. Munir, The influence of pre-ignition processes on the combustion synthesis of nickel aluminides, in Materials Processing by Self-Propagating High-Temperature Synthesis. K. A. Gabriel, S. G. Wax, and J. W. McCauley (Eds), 1987, p. 105. 

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