Reversible Hardening Induced by Electron-Beam Irradiation in CdS Single Crystals

The stress relaxation rate in four-point bending of CdS single crystals has been found to be suppressed by irradiation of 25 keV electron beam. In contrast with the ordinary irradiation hardening, the present irradiation hardening effect, which is named “cathodoplastic effect”, is reversible in the sense that the hardening occurs only while specimens are being irradiated with the electron beam. An in situ observation of dislocation motion was carried out by using the scanning electron microscope the electron-beam probe of which was used also for the electron irradiation on specimens. The comparison of the observation of dislocation motion with the stress relaxation curve shows that the cathodoplastic effect in CdS is attributed to a deceleration of dislocations by the electron-beam irradiation.