Friction Tests don't have to be complicated!

​Two of the simplest tests for friction are the ‘inclined’ and ‘horizontal’ plane tests. They have their uses both inside and outside of their original intended application areas particularly where simple assessment or comparisons of friction are required. Although originally standardised to measure paper and film products the test methods can be used for a wide range of applications for example rail and aerospace verification or quality control tests.

The inclined plane test (ASTM D4918) measures the static friction coefficient (force required to initiate motion) of a known weight block against a surface, which is achieved by inclining the surface until the block moves. Modern digital inclinometers make this test easy to perform.

The ‘horizontal’ plane test (ASTM D1894 & D4917) measures both static friction (force to induce motion) and dynamic friction (force to keep moving) coefficients by pulling a block of known weight across a surface. This test is usually run on an adapted tensile test machine and requires a force transducer and data logging system to carry out.

If you have a requirement for either of these tests or need to discuss something similar, please feel free to call the National Centre of Tribology’s Paul Tweedale on 01925 843476 or email on This email address is being protected from spambots. You need JavaScript enabled to view it..