Development of Nano-Y2O3 Dispersed Zirconium Alloys Synthesized by Mechanical Alloying Consolidated by Pulse Plasma Sintering

Abstract

Zirconium based alloys possesses the low neutron absorption, excellent corrosion resistance, best thermal, excellent mechanical properties and good high temperature applications. Due to this, zirconium based alloys are appealing materials in nuclear and chemical industries. And with addition of Nano-oxide dispersion strengthening the alloys gives better results. In this study the Nano Y2O3 Dispersed Zirconium alloys of composition of 50Zr-25Fe-10Cr-10Cu-5Ti (alloy A), 49Zr-25Fe-10Cr-10Cu-5Ti-1Y2O3 (alloy B) (all in wt. %) are synthesized by mechanical alloying then consolidation in pulse plasma sintering for temperatures 900 ᵒC, 950 ᵒC, 1000 ᵒC. The phase analysis and microstructure were studied during milling and after consolidation by XRD, SEM, EDS. The consolidated product were studied with physical properties like density and porosity test, mechanical properties like Hardness and wear resistance and chemical properties like oxidation resistance.
It is observed from XRD analysis that, crystallite size decreases with increase in lattice strain as milling time increases. The presence of Y2O3 dispersion leads to increase hardness of alloy B than alloy A. but density of alloy B slightly lower than alloy A because of Y2O3 dispersion. The current alloys got higher hardness value than the pure cold-rolled Zr (commercially available) or Zircaloy- 2 (ASTM UNS Grade R60802). Higher hardness product gave good wear resistance. Wear rate of alloy A was more than alloy B which shows that dispersion of Nano Y2O3 possess good wear resistance. And form corrosion study it is observed that the Y2O3 dispersed alloy B shows the excellent corrosion resistant than Alloy A.