We
offer Hard Anodising to BS 5599 standards in blue or black.
Overview: Ideal
for the production of hard wear-resistant surfaces on aluminium
for aircraft and general engineering uses. Typical examples
include cylinder bores, hydraulic & pneumatic piston surfaces,
gears, pulleys, racks and cams.
| Standard |
Thickness
|
| Def
Stan 151-3 |
25-50µm
|
| Def
03-26 |
25-50µm
|
| BS
5599 |
25-50µm
|
Key
Strengths: Key strengths of hard anodising include:
- High
electrical resistance (500 - 1000V)
- Suited
to HE30 grade aluminium
- High
hardness rating 500HV
Limitations: There
are a number of limitations associated with Sulphuric Anodising:
- Restrictions
on types of aluminium suitable for hard anodising. Not suitable
for free cutting aluminium. If uncertain as to suitability
of your aluminium please call. It is worth calling us at
the design stage
- Finished
surface rougher than original, therefore higher quality surface
roughness required of original than desired hard anodised
finish
- Sharp
edges should be radiused before processing as there is always
the risk of thinning, chipping or flaking of the film under
high impact load, particularly on alloys with a high zinc
or magnesium content
Applications: Machinery,
hydraulics and tooling.
Surface
Growth: There is an increase in dimension or surface
growth of between 38 and 50% of the applied film thickness
which must be allowed for at the design stage.
Tanks: We
offer tank sizes up to 8' x 5' x 3'.
Thickness: Standard
coating thickness is up to 75µm.
Finish: Gunpowder
Grey.
Selective
Finishing: Masking can be undertaken to restrict
the hard anodising to the waer resistant surfaces such as
cylinder bores. This process usually involves the sulphuric
or chromic anodising of the non critical areas with the stopping
off of the areas to be hard anodised. This process is then
repeated with the asking reversed.
Fast
Turn Around: We offer a fast turn around because
of the large size of our tanks.
Jigging: Correct
jigging is essential to the resulting finish, and good jig
points are required, a consideration that should be made
at the design stage of a component. The use of loose, sliding
or intermittent contacts will result in an unsatisfactory
connection
and give rise to faults such as thin coatings, burning at
the contact points or even failure to obtain an anodised coating.
|
