What does the process of work hardening do to a metal?

The process of work hardening, also known as strain hardening, involves the increase of a metal's hardness and strength through deformation. When a metal is bent, stretched, or otherwise worked at room temperature, the dislocation structures within its crystalline structure become entangled. This process leads to an increase in dislocation density, which makes further deformation more difficult, resulting in a harder and stronger material.

This characteristic is particularly useful in manufacturing processes where strength is a priority, as it allows components to be shaped more easily initially, before becoming harder and potentially more durable. The other options don't accurately describe work hardening; for instance, softening a metal for machining is more related to heat treatment processes rather than work hardening. Similarly, removing material to enhance tool life or applying coatings to prevent rust do not pertain to the mechanical processes involved in work hardening. Overall, the critical point is that work hardening effectively increases the hardness and strength of metals through physical deformation.