Aflat metal washer is heated. as the washer's temperature increases, what happens to the hole in the center? a flat metal washer is heated. as the washer's temperature increases, what happens to the hole in the center? the hole in the center will remain the same size. changes in the hole cannot be determined without know the composition of the metal. the hole in the center of the washer will expand. the hole in the center of the washer will contract.