Abstract
Results of indentation-induced hardness testing studies on potassium zinc chloride crystals doped with Li+ ions, leading to an understanding of their mechanical behaviour, are presented. The Vickers hardness of these crystals for (100), (010) and (001) planes in the load range 20-160 g were studied. Load-independent values of hardness are estimated for the three crystallographic planes by applying Hays-Kendall's and Li-Bradt models. The results showed that: (1) for the three crystallographic planes the load-independent hardness obtained by Li-Bradt model is higher than that predicted by Hays-Kendall's, approach; (2) the load independent hardness of the (001) plane is higher than that of both (100) and (010) planes, (3) the values of load-independent hardness depend on Li+ concentrations in the K2ZnCl4 crystals, (4) the variations of crack length and crack morphology are described for studied crystal planes. (C) 2007 Published by Elsevier B.V.