|
Letter 5050
Electropolish finish
determination
.
I am looking for a way to quantify the appearance of an
electropolished surface. Generally, in the past, designers call out a
surface finish (micro) to determine the electropolish finish, but
that does not always determine the "brightness" or "reflectivity" of
a surface. The surface may be pebbly but still very bright and
reflective. Is there a surface finish determination that takes these
factors into account? Dave
David McKay
Electrolizing - Cleveland, OH
.
That's a good one!
What's the difference between a bright white painted wall and a
mirror? They may both reflect the same amount of brightness, but the
white wall scatters the reflection and the mirror offers specularity
(angle of incidence equals angle of reflection.
Here, if I understand you right, you want to quantify a type of
quasi-specularity, where you know the surface is pebbled and not
really smooth over a measurable area, so you won't get real
specularity, but you want to quantify the general metallic 'shine'.
I think an observation of the reflection of some kind of screen
might be quantitative enough for you.
|
|
Ted Mooney, P.E.
finishing.com
Brick, New Jersey
|
+
Dave,
There are two ways of qualifying an electropolished finish.
However one way is destructive the other is not. As far as
reflectivity is concerned ,there does not seem to be criteria for
that in particular.It would be safe to say that the smoother the
finish the more reflectivity is going to be. So using a profilometer
to measure the surface smoothness will give you a unit of measure to
set your parameters by. For instance you could say that an 8 micro
inch finish prior to electropolish will give you satisfactory results
but a 12 would not.
Secondly chemical analysis would be your only other option. It is
destructive in nature and is quite expensive. It does serve a purpose
in developing the optimum time, temp and voltage required in the
process. You certainly would not want to use this method of testing
any more than necessary. That test is called ESCA, or Auger.
Well I won't go into that but if you have any questions I can help
with ...
Greg Godbey
Fountain Valley, CA, USA
Dear Reader, please --
- Post a
question on a different subject.
-
- Answer or follow-up on this subject (in non-commercial
fashion).
-
 | 
Save
This Page (why?) - Home - ©1995-2009 finishing.com