What is Strain hardening? strain hardening meaning, Process

What is Strain hardening?

Strain hardening is the process that increases the strength of the metal by changing its crystal structure by inducing plastic deformation. Strain hardening is not a heat treatment process as it is not achieved by heating or cooling the material. Strain hardening is achieved by mechanical forces like rolling or hammering. Strain hardening is also known as work hardening.

Before understanding the Strain hardening, first, understand the term “temper”. Temper is a detail of which types of thermal treatment and cold working is done on the material at the mill. High temper alloy will have less formability than low temper alloys of material because for High temper alloy, Strain hardening capacity has already been used in the cold working process. That’s why formability decreases with increasing temper.

To perform Strain hardening effectively, the material must be performed Annealing heat treatment process. Annealing increases the formability of material by improving its micro-structure. Due to this, material can easily form during work hardening.

Strain hardening process

When a material is deformed, the planes surrounding the atom break their bonds and rebound with another atom at the terminating edge. The dislocation spreads on various planes and all planes are bonded with each other. The density of dislocations increases in metal due to the formation of new dislocations. This will result in restricting the movement of the dislocation and increase the strength of the material.