Development of Y2O3 Dispersion-Strengthened Copper Alloy by Sol-Gel Method

Abstract

In this study, oxide dispersion-strengthened Cu alloy with a Y2O3 content of 1 wt.% was fabricated through citric acid sol-gel synthesis and spark plasma sintering (SPS). The citric acid sol-gel method provides molecular mixing for the preparation of precursor powders, which produces nanoscale and uniformly distributed Y2O3 particles in an ultrafine-grained Cu matrix. The effects of nanoscale Y2O3 particles on the microstructure, mechanical properties and thermal conductivity of the Cu-1wt.%Y2O3 alloy were investigated. The average grain size of the Cu-1wt.%Y2O3 alloy is 0.42 μm, while the average particle size of Y2O3 is 16.4 nm. The unique microstructure provides excellent mechanical properties with a tensile strength of 572 MPa and a total elongation of 6.4%. After annealing at 800 °C for 1 h, the strength of the alloy does not decrease obviously, showing excellent thermal stability. The thermal conductivity of Cu-1wt.%Y2O3 alloy is about 308 Wm−1K−1 at room temperature and it decreases with increasing temperature. The refined grain size, high strength and excellent thermal stability of Cu-1wt.%Y2O3 alloys can be ascribed to the pinning effects of nanoscale Y2O3 particles dispersed in the Cu matrix. The Cu-Y2O3 alloys with high strength and high thermal conductivity have potential applications in high thermal load components of fusion reactors.

Research Progress in Interfacial Characteristics and Strengthening Mechanisms of Rare Earth Metal Oxide-Reinforced Copper Matrix Composites

“…(2) Rare earth elements adsorb other alloying elements and increase the concentration gradient of alloying elements, resulting in local component undercooling and enhanced heterogeneous nucleation of liquid metal matrix. (3) The composition undercooling caused by element segregation results in the formation of segregated compounds and the formation of hetero nucleation sites [ 3 , 45 , 46 , 47 ].…”

“…Internal reinforcing particles in the grain boundary and grain have also been found to enhance concrete strength, refining the grain by a pinning effect. Ke et al prepared copper alloy with Y 2 O 3 content of 1% by spark plasma sintering (SPS) [ 47 ]. The results showed that Y 2 O 3 particles were evenly distributed in the grain, while dispersing nanoparticles in the grain was an effective method to improve strength and ductility.…”

“…The results showed that Y 2 O 3 particles were evenly distributed in the grain, while dispersing nanoparticles in the grain was an effective method to improve strength and ductility. Because grains can form, fix and therefore accumulate dislocations in grains, pinning dislocation and grain boundaries can effectively refine grains and improve the strength and thermal stability of materials [ 47 ]. Yu et al studied the aging characteristics of Cu–0.6Cr–0.15Zr–0.05Mg–0.02Si alloy containing trace rare earth Y [ 48 ].…”

Metallic Materials: Structure Transition, Processing, Characterization and Applications

“…Ke et al [ 21 ] contributed a paper entitled “Development of Y 2 O 3 Dispersion-Strengthened Copper Alloy by Sol-Gel Method”, which demonstrates an oxide dispersion-strengthened Cu alloy with a content of 1 wt.% nanoscale and uniformly distributed Y 2 O 3 particles in an ultra-fine-grained Cu matrix fabricated through citric acid sol–gel synthesis and spark plasma sintering (SPS). The unique microstructure provides excellent mechanical properties with a tensile strength of 572 MPa and a total elongation of 6.4%, together with high thermal conductivity.…”