Investment casting or colloidal technology (Lost wax) 

Investment casting with colloidal technology is the most advanced form of lost wax casting, a method renowned for producing high-precision parts with complex geometries, fine details and smooth surfaces.

Used by Castmetal Advanced Services for the most demanding applications, it achieves tight dimensional tolerances and superior surface quality, making it the preferred process for aerospace, medical, defence and high-tech industrial applications where no compromise is acceptable.

What makes colloidal technology different?

Colloidal investment casting is a precision variant of traditional lost wax casting. In this process, colloidal silica, a dispersion of very fine silica particles in a liquid, is used as the binder to build the ceramic shell around the wax model. This produces a more uniform and robust mould, resulting in better surface quality and more precise tolerances than other lost wax processes.

→ For a more economical lost wax alternative, discover our sodium silicate casting process.

How does the process work?

The colloidal investment casting process uses an aluminium die into which wax is injected to create an exact replica of the part. This wax model is repeatedly dipped into a colloidal silica slurry and coated with fine refractory sand, building the ceramic shell layer by layer. The shell is then steamed to remove the wax, leaving a precise hollow mould. Finally, molten metal is poured into this mould to produce the final part. After cooling, the ceramic shell is broken to reveal the casting.