Viscous flow behavior of selenium

The viscosity of 99.99% pure selenium has been determined over the available range of temperature where crystallization could be avoided. A bending beam viscosimeter was used to obtain data in the high viscosity region, and a rotating cylinder instrument was employed for the low viscosity range. Also determined was the stress dependence of the viscosity at temperatures of 31.5 and 29.6°C. The critical stress for non-Newtonian flow was found to lie in the range of hundreds of psi, which is appreciably smaller than that for oxide liquids in a similar range of viscosity.