Heat treatment. Annealing of steel

Playlist “Materials science“ There are two kinds of annealing: 1st kind annealing and 2nd kind annealing. 1st kind annealing does not depend on the phase transformations in the solid state. Slow cooling is characteristic. There are three types of the 1st kind annealing: • Homogenization or diffusion annealing is used to reduce dendritic or intracrystalline liquation (heterogeneity). • Recrystallization annealing is used to remove metal riveting, i.e. hardening of steel after cold plastic deformation, for example, after pressure treatment. • Stress relief annealing is designed to eliminate the internal stresses that develop in the metal in response to the following processes: casting, rolling, forging or welding. 2nd kind annealing is intended to change the phase composition of steel. As a result, the grain is crushed, the ductility and viscosity of the metal are increased, the strength and hardness are