  Recently reported results on the long lifetime of the tungsten samples under
high temperature and high stress conditions expected in the Neutrino Factory
target have strengthened the case for a solid target option for the Neutrino
Factory. In order to study in more details the behaviour of basic material
properties of tungsten, a new method has been developed for measurement of
tungsten Young's modulus at high stress, high strain-rates (> 1000 s^-1) and
very high temperatures (up to 2650 C). The method is based on measurements of
the surface motion of tungsten wires, stressed by a pulsed current, using a
Laser Doppler Vibrometer. The measured characteristic frequencies of wire
expansion and contraction under the thermal loading have been used to directly
obtain the tungsten Young's modulus as a function of applied stress and
temperature. The experimental results have been compared with modelling results
and we have found that they agree very well. From the point of view of future
use of tungsten as a high power target material, the most important result of
this study is that Young's modulus of tungsten remains high at high
temperature, high stress and high strain-rates.

Materials Science