Development of Ni-base oxide dispersion strengthened alloys using yttria-stabilised zirconia nanoparticles: Powder preparation and spark plasma sintering processing

Abstract

In the present study, nickel-based oxide dispersion strengthened (ODS) alloys were prepared by mechanical alloying (MA) andspark plasma sintering (SPS) using the yttria-stabilised zirconia (YSZ) nanoparticle was used as the oxide additive. Then, the powder samples and consolidated ODS parts were examined using XRD, SEM, and mechanical properties of samples were investigated. The results showed, the lattice strain increases to about 0.461%, indicating that the misalignment density in the particles has risen sharply due to MA. XRD results showed that peak flattening was observed with increasing alloying time to 5 and 10 h. The measured relative density of the parts is 96–98%. The secondary phase in the microstructure was the carbide phase of type M7C3 and MC with an average size mainly less than 5 μm. The highest tensile strength observed in Mo/W containing alloy, which was much higher than conventional alloys such as IN738 and IN939.