Lubrication models of cartilage, and hydrogel inspired by it

In nature, when two solid interfaces contact and slide with each other, adverse friction and wear ensue. Lubrication is an important means to reduce them. Fluid film lubrication and boundary lubrication are the most typical lubrication paradigms that are different in the principle of formation.1 More generally, in fluid film lubrication mode, the two sliding surfaces are completely separated by a fluid film with a thickness much larger than the surface asperities. At this time, the energy dissipation is mainly caused by the fluid being sheared.