The invention belongs to the technical field of added material manufacturing, and discloses an added material manufacturing device and method. The added material manufacturing device comprises a spiral extrusion mechanism; the spiral extrusion mechanism comprises a charging barrel, a first screw rod and multiple sections of heating sleeves, wherein the charging barrel is provided with a solid feedport, a solid conveying area, a melt pressure building area, a melt metering and extruding area, a dispersion area, a storage area and a semi-solid discharge port in sequence from top to bottom; thefirst screw rod is positioned in the charging barrel; a feed end of the first screw rod communicates with a feed port, and the top is connected with a torque sensor; a discharge end is positioned in the dispersion area; and all the sections of heating sleeves sleeve the outer side of the charging barrel corresponding to the solid conveying area, the melt pressure building area, the melt metering and extruding area, the dispersion area and the storage area. Solids are heated and insulated through the multiple sections of heating sleeves to form semi-solids; and the viscosity state and the flowing state of the semi-solids are represented through the torque sensor, so that the problem of incapability of effectively controlling the flowing behavior of the semi-solids in the prior art is solved.