What parameters affect Coefficient of Friction (COF) values?

COF is primarily influenced by the chemical composition of the surface and its surface profile, in packaging, this is often a coating applied to the packaging. Chemical additives are used to adjust the slip resistance, these additives are often waxes or silicones which change the profile on a molecular level and alter the atomic attraction of the surfaces.

Other important factors that affect COF are test speed, the normal force (mass of the sled), contact area and geometry of the sample, these values are often specified in the test method (ASTM D1894 and ISO 8295).