What Is Age Hardening?

Age Hardening

Age hardening, also known as precipitation hardening, is a heat treatment process used to enhance the strength and hardness of steel. This technique involves the formation of extremely small, uniformly dispersed particles (precipitates) a second phase within the original phase matrix. During the process, the steel is first heated to a high temperature to dissolve the alloying elements, then rapidly cooled to create a supersaturated solid solution. It is subsequently reheated to a lower temperature allowing the precipitates to form and grow. These precipitates impede the movement of dislocations within the steel's crystal lattice, significantly increasing its yield strength and hardness.