Solid state additive method

A solid state additive method, forming a coating layer on a base surface by using a consumable rod, wherein the method comprises:

• disposing the consumable rod in a hollow stirring tool, wherein, a cross-section of the consumable rod is round;
• setting a gap between a bottom surface of the hollow stirring tool and the base surface based on a height of the coating layer;
• driving the hollow stirring tool to rotate at a first rotation speed;
• driving the consumable rod to rotate at a second rotation speed, wherein the second rotation speed and the first rotation speed are different in angular speed to form a differential, such that the consumable rod rubs against an inner wall of the hollow stirring tool to generate thermal deformation, to obtain a plastic deformation flow in the hollow stirring tool, wherein a temperature of the plastic deformation flow is lower than a melting temperature of the consumable rod;
• pressing the consumable rod downward to enable the plastic deformation flow to be in friction contact with the base surface;
• and
• translating the hollow stirring tool and stirring the base surface, such that the plastic deformation flow forms a coating layer on the base surface.