Perspective of Wear and Oxidation Resistant Nanostructured Ceramic Oxides for Structural Applications

Abstract

Dispersion of high temperature stable nanostructured Y2O3 in superalloys shows encouraging prospects in improving the mechanical, tribological and high temperature oxidation resistance [1]. Various ceramic oxides such as Y2O3, 50Y2O3-50Al2O3, 50Y2O3-50TiO2, 50Y2O3-50Cr2O3 (in weight%) has been synthesized by mechanical alloying for 20 h in flowing argon atmosphere (flow rate : 100 ml/min). The mechanically alloyed powders are compacted in a uniaxial hydraulic press to fabricate cylindrical pellets. The pellets are consolidated in controlled (Ar/H2) atmosphere to produce bulk compacts. The inert atmosphere synthesis and consolidation hinder the atmospheric oxygen ingress to improve the particle bonding and mechanical properties. The 20 h mechanically alloyed powders show mostly regular and ultrafine particles (<1 μm). The density of the pellets after compaction of all the oxides systems is in the range between 46-56%. Comparative studies of mechanical, tribological and high temperature oxidation of the oxides have been carried out. The present research will provide a roadmap to design ceramic oxides to achieve sustainable structural applications.