adhéziója

Adhéziója is the Hungarian term referring to the adhesion property of a material or interface, i.e., the tendency of a substance to stick to another surface. In practice, it describes the strength and reliability of the bond between two dissimilar materials, such as a coating, adhesive layer, or film and its substrate. The concept encompasses the mechanisms by which adhesion arises and the factors that influence its performance in service.

Adhesion occurs through several mechanisms. Chemical adhesion involves the formation of bonds (covalent, ionic, or hydrogen) at the interface. Physical or secondary adhesion arises from van der Waals forces or capillary effects. Mechanical adhesion results from interlocking between surface roughness or porosity. In some systems, diffusion or interpenetration of polymer chains across the interface can contribute to bonding.

Factors affecting adhéziója include surface energy and cleanliness, chemical compatibility between materials, surface roughness and topography, temperature and humidity, and the presence of surface treatments, primers, or coupling agents. Durability is influenced by aging, environmental exposure (moisture, solvents, temperature cycling) and load history. Adhesion strength is typically assessed with tests such as peel, lap shear, and scratch tests.

Applications span industrial coatings, paints, and structural adhesives; electronics packaging and assembly; automotive and aerospace components; and biomedical devices. In biology, cell adhesion describes how cells attach to each other or to the extracellular matrix via specific receptors, illustrating adhesion across scales from materials science to life sciences.