Solid-phase friction extrusion additive manufacturing spindle system, additive manufacturing equipment and pressure control continuous feeding method

The invention discloses a solid-phase friction extrusion additive manufacturing spindle device, additive manufacturing equipment and a pressure control continuous feeding method. The solid-phase friction extrusion additive manufacturing spindle device comprises a spindle mounting frame, a friction extrusion spindle head and a continuous feeding mechanism. The continuous feeding mechanism comprises two rotary hydraulic clamping mechanisms which are longitudinally arranged and have the same structure, a lower movable hydraulic cylinder, a feeding rotating shaft and an upper movable hydraulic cylinder; the two rotary hydraulic clamping mechanisms are installed on the feeding rotary shaft through the sliding key grooves and can axially move up and down along the sliding key grooves. The upper moving hydraulic cylinder drives the rotary hydraulic clamping mechanism located in the first space to move axially, and the lower moving hydraulic cylinder drives the rotary hydraulic clamping mechanism located in the secon