Ultralow friction and wear of reciprocating systems lubricated by liquid crystalline fluids

Tribological systems that are lubricated with liquid crystals exhibit ultralow friction coefficients and wear. This effect, which has not yet been well examinated and which is even less understood, has been reproducibly observed in reciprocating friction after a certain running-in period and at temperatures around 90° C. Aim of the present work is to study the tribological behaviour of different liquid crystals in more detail. Special focus was on the influence of tribological loading (load, velocity and temperature) on the friction and wear coefficients. Additional surface analysis was performed to correlate the tribological characteristics with surface features. Some attempts were also made to influence the friction coefficients by electrical fields. A better understanding of the trib ological behaviour is essential for the development of efficient production routes and for the qualification of liquid crystalline lubricants for possible future applications