The milled powder is now able to be shaped and compacted. Bill is using a standard hydraulic press to prepare small cylindrical test specimens of 25 mm diameter. Further compressing is needed in order to force the grains of material as close together as possible. An isostatic press capable of developing very high compressive forces is used for this.
Isostatic pressing involves transmission of pressure to the encapsulated sample using a fluid medium.
The effectiveness of this press can be seen in the example of a polystyrene cup before and after isostatic pressing.