“Why does diffusion happen between two solid materials?”
Diffusion is a most fascinating chemical and physical phenomenon, allowing a dense collection of an element to expand and suffuse itself into another. However, What is required for such an effect to occur between two solid items? Well, after many years of research, Materials Scientists and Engineers have discovered a little thing called diffusion couples. Diffusion couples are two items with point defects that are in close contact. When the temperature is elevated, then the atoms of these materials are more likely to moves around, and can “jump” into the holes of its neighboring material. As time approaches infinity, these two materials will become homogeneous with one another, therefore stopping the diffusion process.