Zener relaxation in NaCl:KCl

In metallic alloys the stress-induced reorientation of solute pairs produces an anelastic relaxation called the Zener effect. To determine whether or not this relaxation is also observable in a nonmetallic solid solution, internal friction of single crystals of NaCl plus (1.3% to 1.7%) KCl is measured at 4 to 10 kc/sec. A maximum in the damping occurs near 400°C for nominally pure NaCl and near 300°C for NaCl crystals with CaCl2 added to enhance the cation vacancy concentration. This behavior indicates that the Zener relaxation is present in NaCl. Diffusion constants calculated from this Zener relaxation agree well with the results of radioisotope diffusion experiments. © 1965 The American Institute of Physics.