Microstructures and Properties of Y2O3/La2O3/Cu Composite by Internal Oxidation

Abstract

The 1.5%Y2O3/1.5%La2O3/Cu composite was prepared by oxygen and nitrogen atomization spray deposition technique and internal oxidation. The microstructures, hardness, strength, electrical conductivity and arc erosion surface of the composite were investigated by optical light microscope, scanning electron microscope, micro-hardness tester, tensile test and arc erosion experiment. The results show that, with the increasing of internal oxidation temperature, the grains of the composite grow up obviously. When the internal oxidation reaches to 1000°C, the matrix grains begin to appear annealing twins. The micro-hardness was 436HV, the ultimate tensile strength was 580MPa, yield tensile strength was 503MPa, elongation of alloy was 8.7% and the electrical conductivity was 87% IACS of the composite by internal oxidation at 1000°C for 2h.The arc erosion surface shows a large number of paste-like coagulum and bubbles. Introduction