Surface Finishes

As Cast

“As cast” – parts removed directly from the mould have a surface finish equal to or better than 0.8 micrometres (32 micro inches); this finish may show variable colour.

Chip Rumbling

Removes any sharp edges left after linishing, leaving a surface suitable for most subsequent “finishing” processes.

Shot Blasting

Using stainless steel shot, is generally suitable for brass components and gives a slightly polished surface.

Glass Bead Blasting

Produces a more highly polished surface finish and is most suitable for aluminium parts.

Special Surface Effects

Such as textures and knurling can be incorporated within the Sylatech casting process.

Automatic Grit Blasting

Gives a uniform matt finish, suitable for most subsequent finishing operations.

Applied Surface Treatments

The following treatments can be applied:

Alocrom1200/1000 / Chromate Conversion

Surtec 650 Roche complaint processes which provide corrosion resistance to aluminium parts whilst providing an electrically conductive surface.

Anodising

For protective purposes can be carried out on aluminium alloy castings but cast alloys do not readily accept decorative anodised finishes due to the silicon content.

Plating

Can be applied to most alloys.

Hipping (Hot Isostatic Pressing)

Is used to improve the mechanical properties of aluminium castings by sealing internal voids.

Impregnation

Can be carried out on “as cast” or machined parts where pressure tightness is essential.

Paint/Powder Coating

For protection or visual purposes.

Heat Treatment

Various heat treatments can be applied to harden components. This is carried out generally to aid subsequent machining and enhance component stability. Suffixes to the material grade are used to denote the heat treatment carried out: UK and equivalent USA and EN suffixes are shown below: