annealing

Annealing is a heat treatment process used to improve a metal's ductility and reduce its brittleness. This is achieved by heating the metal to a specific temperature, holding it there for a period, and then cooling it slowly.1

During annealing, a process called recrystallization can occur. This involves the replacement of a cold-worked metal's distorted grain structure with a new, strain-free grain structure. This process is crucial for restoring ductility that may have been lost due to repeated working, such as hammering. Annealing also helps to relieve internal stresses within the metal.21

Radiation can also affect crystal lattices. High-energy particles can dislodge atoms from their normal positions, creating vacancies and interstitial atoms, known as Frenkel defects. These defects can alter the metal's properties, such as decreasing its electrical and thermal conductivity, and increasing its hardness while reducing ductility. Annealing can help to reverse some of these radiation-induced damages by allowing interstitial atoms and vacancies to recombine.3