Statistical Approach for Understanding the Effect of Specimen Size on the Yield Stress and Its Scattering in Mechanically-Alloyed Cu and ODS-Cu Obtained by Micro-Pillar Compression Test

Abstract

Oxide Dispersion Strengthening copper (ODS-Cu) alloy has high strength, high thermal conductivity and superior irradiation resistance which are needed for fusion reactor divertor components. In this study, specimen size dependence of the yield stress in Cu and ODS-Cu which were made by mechanical alloying and hot pressing was investigated by micro-pillar compression test. The distributions of yield stress values were different between the sizes, 1, 3 and 5 µm cubic micro-pillars, which can be explained by the inhomogeneous spatial distributions of both the crystallographic grain in matrix and oxide-particles.

Effect of Alloying Elements on the Microstructure and Performance of Cu-6 pctAg In-Situ Composites

“…However, owing to the insolubility of these oxide particles in molten Cu, oxide-dispersion-strengthened (ODS) Cu alloys cannot be fabricated using conventional ingot metallurgy. [4] Therefore, ODS Cu alloys are fabricated using a complex sequence of procedures including inner oxidation, [5] mechanical alloying, [6] and chemical routes. [7] Consequently, the electrical conductivities of the fabricated ODS Cu alloys at room temperature range from 78 to 92 pct International Annealed Copper Standard (IACS), whereas the tensile strength of most ODS Cu wires ranges from 300 to 700 MPa.…”