The role of experimental parameters in combustion synthesis of NiAl under high gas pressure

High pressure self propagating synthesis (HPSHS) was used to synthesise the NiAl compound. In this paper, the influence of both the kinetic and the thermal effects of the reaction on propagation were studied by using Boddington's model. This analysis was based on experimental results and it shows clearly that pressure and heating rate have great importance in the nature and the stability of the reaction between nickel and aluminium. In effect, we will show clearly the existence of three domains of reaction modes: solid state diffusion, unstable SHS and stable SHS. Additionally, we tried to define the influence of experimental parameters such as grain size of the reactants and porosity of the sample.