Cu-4.2at.% Ti alloy sheets with the dimension of 10×10×0.15 mm3 were irradiated with 2MeV electrons at 200 and 250 °C, and the Vickers hardness was measured as a function of electron fluence. The hardness increased by the electron irradiation. The increase in hardness depends on the electron fluence and irradiation temperatures. The hardening induced by the electron irradiation was observed not only at the directly irradiated surface but also at the reverse side of irradiated surface. By masking an area of specimen surface with a thick copper sheet, we could modify the hardness only for the unmasked area. The atom probe tomography (APT) and the field-emission scanning microscope (FE-SEM) were used for the observation of the microstructures of the specimens. The image of FE-SEM suggests that Ti-rich small precipitates are produced by the irradiation. The present result shows that the electron beam irradiation at elevated temperatures can be a useful tool for improving the hardness of designated areas in bulk Cu-Ti alloys.
ASJC Scopus subject areas
- Physics and Astronomy(all)