Tapadást

Tapadást (Hungarian for adhesion or traction) refers to the ability of two surfaces to stick together or the grip generated between an object and a contacting surface. In physical contexts it covers phenomena from molecular adhesion at solid interfaces to macroscopic traction between tires and road. The term is used in materials science, engineering, medicine and everyday language to describe how well surfaces resist sliding or separation.

Mechanisms underlying tapadást include intermolecular forces (van der Waals, electrostatic), chemical bonding across interfaces, mechanical interlocking due to surface roughness, and capillary forces when liquids are present. Distinct from cohesion (internal strength within a material), adhesion concerns the interfacial strength between different materials. Surface energy, cleanliness, texture, pressure, temperature and humidity all influence tapadást.

Assessment of tapadást employs standardized tests such as peel, tack, shear and lap-shear tests, as well as friction and traction measurements for dynamic applications. Quantitative measures guide selection of adhesives, surface treatments and textures to achieve desired performance.

Practical importance spans automotive traction (tire-road grip), adhesives and tapes, medical dressings, microelectronic bonding and biological adhesion (e.g., gecko feet). Enhancing or reducing tapadást is achieved through coatings, primers, surface roughening, and formulation of adhesives to suit specific mechanical and environmental requirements.