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Understanding Coefficient of Friction

As a service to our engineering customers, General Magnaplate conducts coefficient of friction (COF) testing not only on our synergistic coatings but also on a variety of substrate materials. This friction data can help engineers select combinations of materials that will improve the service life of mating components.

 

Using Coefficient of Friction Values.

Results from our COF testing program include both static and kinetic values. Static values represent the starting friction, while kinetic values indicate the friction with the samples in motion.

Keep in mind that the friction results in this app should only be used as a guide. Real-world friction behavior changes with the application's loading stresses, temperatures, microfinish and environment. These operating conditions are difficult to replicate in standardized lab tests and must be factored in when selecting substrate materials and coatings.

 

Test Conditions.

Our COF testing takes place on a TMI Labmaster Slip and Friction Tester (Model 32-91-00). Test conditions have been standardized as follows:

  • Samples are ground and polished to between 4 and 8 RMS.
  • Laboratory temperature is maintained at 72 F.
  • Each test run consists of 5 readings.


Material grades contained in the Friction Calc include:

  • Aluminum, 6061-t6.
  • Steel, 1032 grade h32.
  • Stainless steel, 304.
  • Titanium -a-, 6ai/4v.
  • Titanium -p-, purity 99.99%, vacuum deposited.
  • Copper.
  • Glass, tempered.
  • Teflon, white, virgin grade.
  • Nickel, autocatalytic 6/8% phos. (0.001).
  • Hard chromium, industrial grade (0.001).
  • Hard anodize, 6061-t6 (0.002).
  • Tufram, proprietary aluminum coating.
  • Nedox, proprietary coating for most base metals.
  • Hi-T-Lube, proprietary solid film metal alloy lubricant.
  • Magnagold, proprietary method for vacuum coating of titanium nitride.
  • Magnaplate HMF, proprietary ultra-hard, high microfinish for most base metals.
  • Magnaplate HCR, proprietary ultra hard, plus exceptional corrosion resistant coating for aluminum.
  • Lectrofluor, proprietary copolymer coatings for maximum chemical resistance applicable to any base metal or combination of metals.

Materials marked with an "A" have undergone a polishing step to approximately 8 RMS after coating. Materials marked with "B" have undergone a post-burnishing step comparable to breaking in the surface.