Hard coating for steel cylinders
Q. I am looking for a coating that will increase the wear on a 1/4" x 1" carbon steel cylinder that has been knurled and case hardened. It is used as a media in tumbling barrels for deburring. We manufacture 100,000 lbs per year.Richard Fontaine
- Enfield, Connecticut, USA
A. The first choice would be hard chromium plate the parts. Another option would be low phosphorous 1-3% P Electroless nickel or a mid-phosphorous EN 5-9% with a bake to increase the hardness.
Atotech - Rock Hill, South Carolina
A. Have you considered using a higher alloy steel that is more wear resistant? Would complete hardening work any better than case hardening?James Watts
- Navarre, Florida
TUTORIAL FOR NEWBIES:
Guillermo is not saying that hardened steel is as hard and wear resistant as chrome plating; rather, he is saying that a significant thickness of hardened steel will outwear a much thinner layer of chrome plating.
For a strong mental image, picture the working end of a bulldozer scraping through stone, dirt, and sand all day: no coating of practical thickness can last long no matter how hard it is, but hardened steel a couple of inches thick will survive a long time.
A. I think the issue here is the same that we frequently point to people that approach us with wear problems. How much wear can you accept or what dimensional control do you have in those parts? If you run them to extinction you should not be looking for a plating but, as James said, a through hardening or a different steel. Plating is generally too thin to compete against 20, 40 or even 100 mils of hard steel no matter how hard is the plating.Guillermo Marrufo
Monterrey, NL, Mexico
I am very supportive of the approach of Mr. Marrufo. In some cases it is best to use high chromium cast iron as we did often.Andrey Igolkin
- St.Petersburg, Russia