A research group led by Prof. Wang Liping at the Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. Li Qunyang at Tsinghua University, developed ...
Nanophysics
Apr 24, 2023
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56
Olefins are key building blocks to manufacture a wide range of value-added products such as polymers, lubricants, plasticizers, drugs, detergent and cosmetics.
Analytical Chemistry
Oct 12, 2022
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3
As climate change warms the planet, glaciers are melting faster, and scientists fear that many will collapse by the end of the century, drastically raising sea level and inundating coastal cities and island nations.
Earth Sciences
Apr 28, 2022
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88
As high-end mechanical equipment put forward increasingly demanding requirements on the high performance characteristics such as bearing-load capacity, working environment and service life of self-lubricating moving parts, ...
Materials Science
Sep 30, 2021
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8
Finding new solutions to address the challenges posed by plastic waste can dramatically improve global sustainability practices and help achieve a greener future. While many researchers are working to solve this problem on ...
Materials Science
Jul 27, 2021
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217
A team of researchers from the University of Kiel in Germany and Aarhus University in Denmark, has found that darkling beetles create a type of lubricant in their legs to prevent their leg joints from wearing away. They describe ...
A team of scientists from the University of Leeds have developed a new hydrogel that has significant potential for oral care products that can help with dry mouth relief.
Materials Science
Nov 17, 2020
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16
A team of researchers at the Weizmann Institute of Science in Israel has developed a lipid-based boundary-lubricated hydrogel that is slipperier than water-based hydrogels. In their paper published in the journal Science, ...
Long-distance cargo ships lose a significant amount of energy due to fluid friction. Looking to the drag reduction mechanisms employed by aquatic life can provide inspiration on how to improve efficiency.
Soft Matter
Sep 15, 2020
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111
In a recent paper in Science Advances, researchers from the University of Amsterdam present new experimental insight into how lubrication works. They have developed a new method using fluorescent molecules to directly observe ...
General Physics
Dec 13, 2019
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6
A lubricant is a substance introduced to reduce friction between moving surfaces. It may also have the function of transporting foreign particles and of distributing heat. The property of reducing friction is known as lubricity.
A good lubricant possesses the following characteristics:
One of the single largest applications for lubricants, in the form of motor oil, is protecting the internal combustion engines in motor vehicles and powered equipment.
Typically lubricants contain 90% base oil (most often petroleum fractions, called mineral oils) and less than 10% additives. Vegetable oils or synthetic liquids such as hydrogenated polyolefins, esters, silicones, fluorocarbons and many others are sometimes used as base oils. Additives deliver reduced friction and wear, increased viscosity, improved viscosity index, resistance to corrosion and oxidation, aging or contamination, etc.
Lubricants such as 2-cycle oil are added to fuels like gasoline which has low lubricity. Sulfur impurities in fuels also provide some lubrication properties, which has to be taken in account when switching to a low-sulfur diesel; biodiesel is a popular diesel fuel additive providing additional lubricity.
Non-liquid lubricants include grease, powders (dry graphite, PTFE, Molybdenum disulfide, tungsten disulfide, etc.), teflon tape used in plumbing, air cushion and others. Dry lubricants such as graphite, molybdenum disulfide and tungsten disulfide also offer lubrication at temperatures (up to 350 °C) higher than liquid and oil-based lubricants are able to operate. Limited interest has been shown in low friction properties of compacted oxide glaze layers formed at several hundred degrees Celsius in metallic sliding systems, however, practical use is still many years away due to their physically unstable nature.
Another approach to reducing friction and wear is to use bearings such as ball bearings, roller bearings or air bearings, which in turn require internal lubrication themselves, or to use sound, in the case of acoustic lubrication.
In addition to industrial applications, lubricants are used for many other purposes. Other uses include cooking (oils and fats in use in frying pans, in baking to prevent food sticking), bio-medical applications on humans (e.g. lubricants for artificial joints), ultrasound examination, internal examinations for males and females, and the use of personal lubricant for sexual purposes.
This text uses material from Wikipedia, licensed under CC BY-SA
