What is internal friction?

Internal friction, also known as dynamic friction, is the resistance to motion that is generated within a material as a result of the interactions between its particles. This type of friction is typically caused by the movement of dislocations or defects within the material's crystal lattice structure, and it can result in energy loss, heat generation, and deformation of the material. Internal friction is influenced by a number of factors, including the temperature, the frequency and amplitude of the applied mechanical stress, and the type of material being used. It is an important property in materials science and engineering, and it is often used to measure the mechanical properties of materials and to assess the durability of structural components.