if a metal wire is loaded with a force such that it is still in the elastic limit. when it gets deformed some energy gets stored in it due to worke done by the force.

Whenever we apply force to an object, it will cause deformation. If the deformation caused is within the elastic limit, the work done in deforming the object is stored within it as elastic potential energy.

We call this (elastic) 'strain energy'.

 

It can be released from the object by removing the applied force. The strain energy then performs work in un-deforming the object and returns to its original state.

 

If the deformation is within the elastic limit, the energy gets recoverd. It also depends on the type of material.

 

For example, rubber gives up less energy than the energy it takes up to deform.  The difference between these two energies is the energy lost.

 

This energy loss is absorbed by the molecules of rubber and is eventually dissipated as heat. Consequently the rubber gets noticeably hot if we stretch it and un-stretch it repeatedly.