No passwords, No popups, No cost
we earn from your eBay & Amazon purchases

Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Adver-
tise
Help
Wanted
Current
Q&A's
Site 🔍
Search
curated with aloha by
ted_yosem
Ted Mooney, P.E. RET
- Pine Beach, NJ
finishing.com -- The Home Page of the Finishing Industry


  pub
  The authoritative public forum
  for Metal Finishing since 1989

-----

Enhancing the reflectivity of mirror polished stainless





1998

Are there any ways to enhance the reflectivity of mirror polished stainless? We specialize in mirror polished stainless steel sheets. Surface quality is close to a glass mirror, but reflectivity wise, it tested at only 62-63%. Type of stainless involved are 304 and 316.

Thank in advance for comments and suggestions.

Michael Liu Taylor
Michael Liu Taylor
specialty stainless steel distributor - Dallas, Texas



"Handbook of Physical Vapor Deposition (PVD) Processing"
by Donald Mattox

on AbeBooks

or eBay or

Amazon

(affil links)

I am afraid that chromium has a naturally high adsorption for solar radiation. To increase the reflectivity you will have to change the composition of the surface. Silver has about the highest solar reflectance but aluminum is good.

Donald M. Mattox
Society of Vacuum Coaters
Albuquerque, New Mexico
Donald is the author of:
"Handbook of Physical Vapor Deposition (PVD) Processing" (2010) [on AbeBooks or eBay or Amazon affil links]
and "The Foundations of Vacuum Coating Technology" (2018) on AbeBooks or eBay or Amazon affil links]
1998



I have been trying to develop a mirror for outdoor use (on a sundial) that will withstand the rigors of weather. Would bare Stainless steel retain a good surface mirror over many years? How about chrome plated, or nickel plated stainless steel? I have tried hard gold plating, but it seemed to dull easily. I have had some luck with rhodium, but it chipped off the underlying nickel plated steel too easily, and is expensive. Bill Gottesman

William Gottesman
sundials
1999



Bill, IMHO, you can't beat stainless for corrosion resistance in exterior applications. Mirror polished stainless are used in many exterior applications. Titanium gold colored stainless (TiN) are used in signage system on high rise buildings. Ti gold will outlast gold plating on automobile applications. Clean stainless steel surface will self generate a oxidizing layer to protect itself from rust and corrosion.

Michael Liu Taylor
Michael Liu Taylor
specialty stainless steel distributor - Dallas, Texas
1999


Mike, while Silver and/or Rhodium are probably the best metals to use for visible light reflectance with reflectivity of rhodium often above 90% and have excellent wear/environment protection, they are expensive. An economical choice yielding moderate to good performance is a hi-phosphorous electroless nickel with reflectivity about 80%+ it is often used to protect against corrosion in marine environments and as a surface coat for many precision optical components. Many e-less nickels will pass 1000 hr. salt fog tests

Anthony J. Covey
electroformer - Corona, California
1999



on -- Don Mattox wrote "I am afraid that chromium has a naturally high adsorption for solar radiation. To increase the reflectivity you will have to change the composition of the surface. Silver has about the highest solar reflectance but aluminum is good. "

The quest for one piece metal solar mirrors goes on. What would be extremely useful for photovoltaic concentration is a mirror that reflects UV but not infrared. What is the absorption spectrum of chromium? Even if stainless is lower in total reflectance than aluminum or silver, if it reflects heat differently than UV it has an excellent application.

Robert Carlson
mfr solar mirrors - Pt Richmond, California
2003



Apparently, the "shininess" of nickel chrome electroplating has more to do with the smoothness and leveling of the nickel plating than with the solar reflectance. Chromium plating is used for solar collectors rather than reflectors, although the absorbtivity can be optimized further with "black chromium" plating.

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey


Hello, what about the reflectivity of mirror finished 316 in infrared? Is there any instrument to easily measure it? Thanks.

Fabrizio Goi
- Italy
September 21, 2011




(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

Finishing
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g,
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"