tribological

Tribology is the science and engineering of interacting surfaces in relative motion. It encompasses the study of friction, wear, lubrication, and the ways to control sliding, rolling, and fluid interactions. The field integrates mechanical engineering, materials science, chemistry, and surface engineering to improve efficiency, reduce heat and noise, and extend component life.

Friction is the resistive force that opposes motion between contacting surfaces; wear is the progressive material loss due to mechanical action. Wear mechanisms include adhesive wear, abrasive wear, fatigue wear, and corrosive wear. Factors such as contact pressure, temperature, surface roughness, lubrication, and environmental conditions influence friction and wear.

Lubrication reduces friction and wear by introducing a lubricant layer between surfaces. Lubrication regimes are categorized as boundary, mixed, hydrodynamic, and elastohydrodynamic, depending on the film thickness relative to surface roughness. Lubricants can be liquids, gases, or solids, and are selected based on operating conditions. Common testing methods include pin-on-disk and ball-on-flat tribometers to measure friction and wear.

Applications span bearings, gears, seals, cam-follower systems, cutting tools, and biomedical devices. Tribology also covers surface engineering and coatings designed to reduce wear and lower friction, such as diamond-like carbon and ceramic coatings. Current research areas include micro- and nano-tribology, wear prediction and modeling, coating lifetimes, and the environmental impacts of lubricants. The objective is to optimize performance, energy efficiency, and reliability across engineering systems.

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