Synthesis of (TiB₂)_PNi/ Ni₃Al/Ni gradient material via field-activated combustion

(TiB₂)_PNi/(TiB₂)_PNi₃Al/Ni₃Al/Ni gradient materials were prepared by mechanical alloying (MA) and field-activated pressure-assisted synthesis (FAPAS) . The effects of the electric field to synthesis and diffusion of layers have been investigated. The microst ructure and the phase composition of the interfaces and the microhardness of the gradient materials were characterized. The results show that it is feasible for the four-layered gradient materials samples of (TiB₂)_PNi/(TiB₂)_PNi₃Al/Ni₃Al/Ni  to be produced by FAPAS process，and that this method is fast，simple and the product is of uniformity. Concent ration profiles of elements across the interfaces of the layers show significant inter-diffusion and good metallurgical bonding. The measured microhardness values of the sample increase smoothly from the side of the nickel subst rate to the surface layer .