Description
This thesis investigated the current activated tip-sintering of reactive mixtures of nickel and titanium to form Ni-Ti intermetallics. The effect of elemental powder composition, heating profile and micro-jet inert gas pressures on the developed macro- and microstructure was investigated. The heating profile brought upon by selective electric current application was found to have a significant effect on whether the reaction is a volumetric combustion or a self-propagating high temperature one. The best results in terms of homogeneity and Ni-Ti intermetallics yield, were obtained for an inert gas pressure of 4 psi under for the nickel rich composition. In addition, surprising results at the higher inert gas pressures show the formation of hollow products, which can give rise future exploration of this technique for combustion synthesizing hollow products of different shapes.
