The optimization of Cu6Y sourced ODS-Cu: Effect of Y2O3 content

Abstract

To refine the dispersive Y2O3 particles and to explore the optimum Y2O3 content, reducing the Y2O3 addition from 1.5 wt% to 0.5 wt% for Cu6Y sourced Cu-Y2O3 was investigated. It was found that reducing the Y2O3 addition had little influence on the number density, while reducing the size of the Y2O3 particles. Compared with the Y2O3 addition, the nucleation point is expected to be more important for the number density of the Y2O3 by the in-situ fabrication method. Moreover, reducing the Y2O3 addition indeed thinned the prior particle boundaries with O enrichment and contamination, thereby improving the mechanical performance and thermal conductivity. It was calculated that dispersion strengthening made great a contribution to the increment of the yield strength for ODS-Cu. While, the large particles with contamination on the prior particle boundaries induced the dimples and the premature micro-cracks, deteriorating the tensile performance. Therefore, the performance of Cu6Y sourced ODS-Cu can be improved once further reduces the introduction of contamination and suppresses the growth of MA powders during MA process.