Special Sands

What are special sands?

The term “special sand” covers all industrial minerals (except quartz sand) commonly used in foundries as moulding material for the manufacture of cores and moulds/dies.

Special sands include natural mineral sands, sintering and melting products produced in granular form or turned into granular form by breaking, grinding and grading processes, or inorganic mineral sands produced by other physical-chemical methods.

Special sands are different from quartz sand, particularly as regards their significantly lower thermal expansion behaviour within the temperature range of 20 – 600°C, their heat conductivity, refractoriness, and other physical characteristics.

Reasons for using special sands

Special sands are used instead of quartz sand for coremaking and mouldmaking because they are characterized by better physical-chemical properties.

In consideration of the casting properties to be achieved, the individual advantages of a special sand can be used

  • to avoid sand expansion defects, especially finning/veining;
  • to avoid the addition of gas-forming ingredients;
  • to avoid a mould-metal interface reaction;
  • to avoid metal penetration;
  • to reduce the core weight;
  • to increase the flowability of the sand;
  • to control the formation of microstructure;
  • to produce thin-walled castings.

Overview of HA Special Sands

Aluminosilicate sands Material
J Sand natural mineral mixture
Kerphalite KF natural mineral
Cerabeads sintered ceramics
Chamotte sintered ceramics
M Sand oxide ceramics
Bauxite sand oxide ceramics
Heavy mineral sand
R Sand natural mineral
Technical ceramics
SiC non-oxide ceramics

Kerphalite KF: Special Sand for High Performance Castings

Due to its particular characteristics silica sand has its limits as a moulding material when it comes to casting finely structured components, reduced wall thicknesses and perfect surfaces. Thanks to its high temperature load strength and a strong resistance to metal penetration, Kerphalite™ KF, a special sand, has proven itself suitable for these types of applications in many foundries. 

Please read our full product article.

Contact

Our product management team will be happy to provide you with detailed information and answer any questions on our Special Sands:

Tel:     +49 211 5087 -213 / -214 

Fax:    +49 211 50 77 57

E-Mail: pm@huettenes-albertus.com

Special Sands

Technical Article:

Special sands - Base materials for state-of-the-art cores and moulds

(2008)