Comprehensive study on the sintering behavior of yttria nano-powder in contact with electrolytic iron using the rapid solidification processing technique

Oxide dispersion strengthened (ODS) steels are considered as the future structural material of interest for nuclear power plants, due to their elevated creep resistance at higher operation temperatures. In this study, a 0.3 wt% nano-yttria (Y2O3) dispersed iron cast trial was elaborated using rapid solidification processing (RSP). The nano-sized Y2O3 particles were introduced into the iron matrix using the formulation of a low-concentrated colloidal dispersion. The aim of this study is to understand the dispersibility behaviour of the ceramic Y2O3 nano-powder when added to an iron melt as a colloidal dispersion, during high-temperature melting or RSP. It was found, after casting the iron/Y2O3 composites, that apart from an inhomogeneous dispersion, super-micron agglomerates alternate dispersed zones. Overall, this study tried to assay the casting practice of iron/Y2O3 composites using RSP. As an overall conclusion, it can be stated that wettability in synergy with porous materials characteristics, (especially powder purity) seems to have a significant impact on the dispersibility of Y2O3 particles and its super-micron sphere formation behavior in an iron melt.