Cohesion - definition

Cohesion is a physicochemical phenomenon involving forces of attraction between molecules of the same substance, resulting mainly from electrostatic interactions, van der Waals forces and, in certain cases, hydrogen bonds. Cohesion forces are responsible for the structural integrity of solid and liquid bodies, determining their mechanical properties such as tensile strength, viscosity, surface tension or elastic modulus.

In liquids, cohesion manifests itself in the form of surface tension, which causes the surface of the liquid to behave like an elastic membrane, minimising its surface area under the influence of internal attractive forces. In solids, especially crystalline and polymeric materials, cohesion affects structural integrity and deformation and fracture mechanisms.

In materials science and surface engineering, cohesion plays a key role in the design of composites, Protective Coatings, adhesives and adhesive technology, where it is important to ensure high internal material cohesion. In the context of chemical engineering and process engineering, the analysis of cohesion forces allows the optimisation of parameters for sedimentation processes, phase separation and the control of rheological properties of suspensions and emulsions.

At the microscale, cohesion is described using molecular mechanics models that take into account short- and long-range interactions, while at the macroscopic scale, its effects are studied within the framework of solid state physics, surface chemistry and materials engineering. Cohesion is also a key concept in geotechnical sciences, where it refers to the cohesion forces of soil particles, affecting the stability and shear resistance of the soil.

Transfer Multisort Elektronik (TME) is one of the world’s largest global distributors of electronic components, electrotechnical parts, workshop equipment, and industrial automation. The catalog includes over 1,500,000 products from 1,300 leading manufacturers. TME’s modern logistics centers in Łódź and Rzgów (Poland), with a combined area of over 40,000 m², ship nearly 6,000 packages daily to customers in more than 150 countries.

TME also invests in the development of knowledge and skills of young engineers and electronics enthusiasts through the TME Education project, and supports the tech community by organizing the TechMasterEvent series, promoting innovation and experience exchange.