Definition - What does Cohesion mean?
Cohesion is the mutual attraction and sticking property of molecules. It is an intrinsic property in certain substances that is commonly caused by the structure and shape of its molecules, resulting in electrical attraction.
Cohesion paves the way for surface tension, establishing a solid-like condition where, in low density or light, materials can be set.
Cohesion is also known as cohesive force or cohesive attraction.
Corrosionpedia explains Cohesion
Cohesion promotes attraction between dissimilar molecules. This concept has many applications, the most common being its role in promoting coating strength. The strength in coatings refers to its cohesion measure to a substrate or surface. Without good cohesion, the coating is useless. As long as coatings remain sticking to the surface, the material is protected against:
- Weather and environment
- Stress and scratches
The performance and durability of coatings greatly relies on cohesion. With this example, cohesion can be defined as the material's inner strength and is identified by the strength of the molecular forces.
Therefore, industries perform cohesion testing to evaluate the adhesion and cohesion properties of paints. This may include tests like the scrape adhesion test, that gauges adhesion tenacity when coated on flat and smooth panel surfaces. This test along with others ensures that coatings adhere appropriately to the coated surface.