Appts. for exerting high pressure on material sample - which has anvil loaded on bearing surface tapering inwardly away from pressure-exerting point of anvil

摘要

The anvil has a main axis perpendicular to the pressure-exerting point, about which the anvil is pref. a solid of revolution. The anvil is loaded by a member, pref. in the form of a ring, bearing on one face of the anvil, and this face is inclined relative to the axis, tapering axially inwardly away from the point. the anvil can be formed of materials other than the usual diamond, e.g. boron or boron nitride or carbide. The bearing face of the anvil pref. makes an angle greater than 13 degrees with the axis, and an insert of a plasticity deformable material can be interposed between the face of the anvil and the opposed face of the loading member. In this case, the two faces are slightly convex so that the gap between them is smallest at the centres of the faces. The gap between the faces at any given point can be chosen according to the desired pressure at that point and the mechanical properties of the materials of the anvil, loading ring and the insert. Appts. is used in the study of the properties of materials when subjected to very high pressure. The tapering bearing surface ensures that the anvil is correctly aligned, and so the anvil can be made from cheaper, non-transparent, materials. Also, space no longer needs to be felt around the anvil to allow the passage of light, and so the anvil can be made stronger and thus less prone to failure.