Abstract:
Ferritic steel with oxide dispersion strengthening (ODS) is a promising material for
fusion and fission reactor components. In this study, the influence of Zr, V, Mo on yttria
dispersed ferritic alloys was analysed. The powders were developed by using mechanical
alloying (MA) and subsequently consolidated by spark plasma sintering (SPS) at different
temperatures (900°C, 1000°C & 1050°C) in argon atmosphere. The densification of the alloys
was found to improve significantly with increase in the sintering temperature. The maximum
relative density was found to be 97.5-98.3% with samples sintered at 1050°C. Microstructural
analyses, carried out by optical and scanning electron microscopy (SEM), showed random
orientation of grains with bimodal grain size distribution. X-ray diffraction phase analysis
showed the presence of bcc ferritic phase in which Y-Ti-O, TiO and Ti-Cr-O oxides were
dispersed and this was confirmed through transmission electron microscopy (TEM). Further, the
hardness value obtained by nanoindentation was correlated with the compressive strength and
wear resistance. The results have been analysed in terms of alloying and strengthening
mechanisms
