A friction test determines how much force is needed to push a material in motion and slide it against a testing surface. Materials testing companies can look at how much force is required to get the material in motion and keep it moving. This testing is also useful for looking at wear properties of components like lubricants. It may be required for labeling purposes, and can also be important for research and development, even if friction test information is not provided to members of the public.
In a basic friction test, the sample material is placed in a machine that can exert precisely calculated and measured force. It pushes the material against a testing surface, usually made from a different material. A technician can observe the testing, taking note of when the sample starts to move and how much force was required to move it. The equipment can also determine how much force is needed to maintain the motion, to keep the material from stopping.
One important application of a friction test is in the development of products that need to move through rollers and similar equipment. This can include paper for printing, plastic used in packaging, and so forth. If these materials require too much force to move, they can jam, causing problems on a production line. Extremely slippery products may come with their own issues, like feeding too quickly and creating snarls.
People can also use friction testing to collect information about the properties of materials used in applications where safety may be a concern. Flooring and paving, for example, cannot be too slick, because if they are, people might fall. In this type of friction test, operators might try a dry test or one with spilled materials like water and oil. This ensures that products like kitchen flooring will be safe to use not just in optimal conditions, but also when people have spilled things on the floor.
Plastics can be subjected to friction testing to find out more about how they will perform in active use. This can include wear testing to see how much force is required to damage the plastic. In the case of lubricants, testing equipment may be rotated or agitated at high speed to simulate environments like engines. This can help test operators determine when the lubricant starts to fail. The results determine the rating of the lubricant, which is important for drivers and mechanics who want to select the right material for their needs.