3. Moulding methods

3.1 Permanent pattern graphite casting

• Principle (figure 6 )

  This method is similar to traditional sand casting. A graphite powder is pressed against a wooden, resin or metal half-model using a pneumatic rammer or hydraulic press. This graphite powder has previously been mixed with an organic binder, which causes the graphite to set after a few minutes when cold, or at a temperature of 200-300°C (in the latter case, a thermosetting resin is used). The graphite lump bearing the model impression can then be demolded. The remolding operation then consists in assembling the individual graphite lumps to form the complete mold, which may in some cases...