Strength studies on V and Ta-W alloys using Diamond Anvil Cell*

The pressure-dependences of the quasi-static yield strength of polycrystalline forms of V and Ta-W alloys have been measured at room temperature using an implementation of a non-hydrostatic diamond anvil cell technique. A new feature of this work is the use of \textit{in situ} determination of the sample thickness and pressure with synchrotron X-ray. We adopt the conventional technique [C. Meade and R. Jeanloz, J. Geophys. Res. 93, 3261 (1988)] and the pointwise approach to determine the strength under Tresca yield criterion. The result shows the trend of the pointwise analysis is similar to the one of conventional approach.