Search results
Results from the WOW.Com Content Network
Motor oil, a common lubricant. A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, transporting foreign particles, or heating or cooling the surfaces.
Synthetic lubricants were first made in significant quantities as replacements for mineral lubricants (and fuels) by German scientists in the late 1930s and early 1940s, because of their insufficient quantities of crude needed to fight in World War II.
A true grease consists of an oil or other fluid lubricant that is mixed with a thickener, typically a soap, to form a solid or semisolid. [1] Greases are usually shear-thinning or pseudo-plastic fluids, which means that the viscosity of the fluid is reduced under shear stress.
The compound is classified as a transition metal dichalcogenide. It is a silvery black solid that occurs as the mineral molybdenite, the principal ore for molybdenum. [6] MoS 2 is relatively unreactive. It is unaffected by dilute acids and oxygen. In appearance and feel, molybdenum disulfide is similar to graphite.
Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum, [1] as distinct from usually edible vegetable oils. The name 'mineral oil' by itself is imprecise, having been used for many specific oils over the past few centuries.
The lubricity of a substance is not a material property, and cannot be measured directly. Tests are performed to quantify a lubricant's performance for a specific system. This is often done by determining how much wear is caused to a surface by a given wear-inducing object in a given amount of time. Other factors such as surface size ...
Diamond is the hardest mineral known (10 on the Mohs scale), but graphite is one of the softest (1–2 on Mohs scale). Diamond is the ultimate abrasive, but graphite is soft and is a very good lubricant. Diamond is an excellent electrical insulator, but graphite is an excellent conductor.
The Mohs scale of mineral hardness, based on scratch hardness comparison, defines value 1 as the hardness of talc, the softest mineral. When scraped on a streak plate , talc produces a white streak, though this indicator is of little importance, because most silicate minerals produce a white streak.