I did a lab experiment where I was testing the hardness of copper alloys when reducing the materials thickness. My results show that the more the materials thickness was reduced, the harder the material became. Why is this?
copper for example exhibits work hardening which strenghtents material that is being deformed. it is result of defects caused by movements of atoms along slip planes (defects act as rivets restricting degrees of motion for slip planes). to release this stress, you need to apply heat for prologned time and material will return to original (soft) state.
