Radiation Hardening in Alkali‐Halide Crystals

摘要

Hardening by gamma irradiation was investigated in eleven alkali halides with the rocksalt structure. The linear dependence of the flow stress upon the one‐half power of the F‐center concentration, as previously observed in LiF and KCl, was also observed in these new substances. (The earlier experiments showed that the hardening is not actually caused by F cneters but by a defect resulting from F‐center production.) The rate of hardening with concentration was found in all cases to be consistent with that to be expected for non‐symmetrical defects. Comparisons were also made between the amount of hardening per defect and the lattice spaces available to certain specific defects. The only clear correlation was with a halogen atom in the interstitial space at coordinates 0, ¼, ¼ in the unit cell.