Aluminium Anodisers for 50 years
PROPERTIES
Anodised aluminium surfaces are extremely hard-wearing and abrasion resistant and provide corrosion protection. Anodised surfaces are reputed to be second only to a diamond in hardness.
The thickness of an anodic coat varies from 5 microns to 25 microns depending on application requirements.
Anodised Aluminium application:
| 5 microns thickness | is suitable for indoor decorative end use |
| 12-15 microns thickness | is used for the majority of architectural and industrial applications |
| 25 microns thickness | is recommended for permanent exterior uses where there is severe coastal salt exposure or an industrial environment. |
THE PROCESS
Anodising is an electro-chemical process in which aluminium is made the anode in a sulphuric acid solution containing additional proprietary additives.
The work is suspended on special racks and receives a series of surface preparation treatments in separate tanks including hot alkali cleaning, hot caustic soda etching and de-smutting. The work is then transferred to the anodising tank, where a low DC voltage – 21-24 volts – is applied.
At this stage a permanent silver finish can be applied to the work by placing the rack in a tank containing a special chemical sealer.
Alternatively, the rack can be transferred to a tank for a further electrolitic process in which a deposit of tin is applied. The length of this process will determine the depth of colour, from light to deep bronze and ultimately black. A final sealing process follows.
| Colours | Silver, champagne, light to dark bronze and black |
| Capacity | Anodised Aluminium extrusions of up to 6 metres |
| Batch anodising | Small components |
| Thickness | 12 to 25 microns |
Phone +64 4 388 1091 Email: sales@alexco.co.nz
