A method for creating a solid state joint is disclosed. The method includes providing an adjoining apparatus that includes a pin tool, a backing plate and a thermal control plate disposed below the backing plate. The method also includes rotating the pin tool and traversing the pin tool relative to a workpiece along a joint to be welded on the workpiece. The method further includes manipulating the temperature of the pin tool and the backing plate in order to control the temperature and rate of change of temperature experienced by the workpiece at a weld affected zone at the joint. The method also includes maintaining a user chosen temperature differential between the weld affected zone and the backing plate via the thermal control plate.