tribokemi

Tribokemi, or tribochemistry, is the study of chemical processes that occur at the interface of contacting surfaces under mechanical action such as sliding or rolling, where friction, pressure and sometimes high temperature drive chemical reactions. These reactions can modify surfaces and form tribofilms that influence friction and wear. The field combines tribology and surface chemistry and is concerned with both fundamental reaction mechanisms and practical outcomes in lubricated and dry contacts.

During tribological contact, mechanical energy can break chemical bonds and generate reactive species, leading to oxidation, sulfidation, phosphorylation, polymerization or cleavage of lubricant additives. The result is protective or detrimental films on surfaces. Environmental conditions such as oxygen, humidity, temperature, and the chemical nature of the lubricant strongly affect the pathways and products.

Applications include automotive and industrial lubricants, where additives such as ZDDP, MoDTC, sulfurized esters, and solids like graphene form tribofilms that reduce wear and modify friction. Tribochemistry also explains wear of materials under extreme conditions and the design of surfaces and additives to promote desirable chemistries.

Studying tribokemi relies on analytical tools like X-ray photoelectron spectroscopy (XPS), Raman and infrared spectroscopy, scanning Auger, time-of-flight secondary ion mass spectrometry (ToF-SIMS), and electron microscopy, often with in situ tribology experiments. Computational approaches, including density functional theory and reactive molecular dynamics, help predict reaction pathways and film formation.

The field has grown with developments in advanced lubricants and surface engineering, contributing to longer component life, energy efficiency, and reduced environmental impact.