plating, anodizing, & finishing Q&As since 1989
Coefficient of friction for Electroless Nickel Plating (EN)
Q. We are using electroless nickel for electrical conductivity across a bolted joint. What thickness would you recommend and what friction can I expect with nickel-to-nickel contact?Paul Dizon
aerospace engineering - Ellicott City, Maryland, USA
A. Electroless nickel (EN) deposits are low friction hard materials. EN against EN will not gall, unlike other metals and alloys that are mated in motion. I do not know the coefficient of friction off hand, but there is published information. The friction varies with phosphorus content. Generally the higher P in the alloy the lower the friction. Note that EN deposits are brittle and subject to cracking at very high loads. The Nickel Development Institute has published data on coefficient of friction, as does International Nickel Co.
Consultant - Poulsbo, Washington
(Don is co-author of "Plating on Plastics" [affil link to the book on: Amazon or AbeBooks ])
A. High phosphorus Electroless nickel should be around 0.2 CoF.Michael Zuraw
- Georgetown, Ontario
A. The coefficient of friction of EN vs EN is 0.38 to 0.45 in a non-lubricated condition. With lubrication, the coefficient of friction drops to 0.2.
EN will gaul against EN unless one coating is heat treated so that the hardness of one surface is at least 150 HV different from the other.
Ron Duncan [deceased]
- LaVergne, Tennessee
It is our sad duty to note Ron's passing on Dec. 15, 2006. A brief obituary opens Episode 13 of our Podcast.
Q. I'm Ph.D. student at University of Ljubljana, Faculty of Mechanical Engineering in Slovenia. I'm interested in coefficient of friction. I wonder if somebody knows the coefficient of friction between Nickel/Teflon plating and Nickel/Teflon plating. I would be very grateful for the information.Janez Benedicic
Want rough electroless nickel plated surfaceOctober 21, 2015
Q. I want to ENP coat a steel component of a vibration mount that has a Neoprene rubber damper element contacting it. The problem we currently have is that the ENP has a very low friction coefficient against the rubber, and the rubber element is sliding against the coated steel element. I understand that zinc plating is generally used for coating steel in vibration mounts. What methods if any can be used successfully to roughen up an ENP surface to increase its COF?
VEEM Ltd - Western Australia, Perth, Australia
A. Hi Paul. It is relatively common to occlude particles like silicon carbide into an electroless nickel coating; I would think that this should give you roughness to grip the rubber.
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey