Moulding Base Materials

Moulding material terminology

Primary constituent for the production of moulding materials for lost
moulds and cores:

• Moulding base material
• Moulding sand binder
• Moulding material additives

Moulding base material:
Consists of natural mineral or synthetic granulates or sand:

• The moulding base material is a granular aggregate material with certain granulometric properties
• The grain diameter is between 0.02 and 2.0 mm
• The moulding base material forms the framework of a mould

Moulding sand binder and hardener
Connects the single grains of the moulding base material by forming bridging bonds between them:

• Swelling binder (clay/bentonite that swells when water is added)
• Ceramic binder (alumina solidifies by drying or sintering)
• Hydraulic binder (gypsum or cement reacts with liquid and hardens)
• Chemical binder, inorganic or organic (chemical reaction and solidification)

Bridging bond:
Forms the connection between the grains of sand, holding the mould together:

• Depends on adhesion on the grain surface due to adhesive forces
• Load capacity of a bond: maximum contact surface and formation of optimum layer thickness

---

10 Pages