Designing tapered anvil apparatus for achieving higher pressures

An analysis is made for tapered anvils of ultrahigh-pressure apparatus in terms of the loading distribution on the face and flanks that would generate stress fields within the body of the anvil which are within the strength capability of the anvil material. To attain the highest possible face pressures the hardest and strongest materials must be used for the anvils, and in addition, the pressure of the gaskets against the tapered flanks must follow a proper gradient. The pressure performances of various actual apparatuses are presented to compare with the suggestions of the analysis. Using diamond anvil material together with optimum gasket geometry and structure it seems that useful apparatus pressures as high as one megabar (10⁵ GPa) are possible.