3D printing dispensing extruding device capable of realizing online alloying

The invention discloses a 3D printing dispensing extruding device capable of realizing online alloying. The 3D printing dispensing extruding device comprises an online dispensing mechanism and a plurality of molten metal extruding spray heads. The online dispensing mechanism comprises more than one storage compartment, a feeding device, a mixing compartment, an air supply device, an online molten metal component detection device and a PC. The six molten metal extruding spray heads are communicated to the bottom of the mixing compartment through conveying pipes, and a screw extruding mechanism is arranged inside each extruding spray head, so that the real-time controllable extrusion of the molten metal can be realized. In the working process, the current layer material information is firstly printed according to 3D, the preparation, mixing, melting and online detection of a metal raw material are carried out by the online dispensing mechanism, when the molten metal component meets the requirement, the molten metal is led into the extruding spray heads through conveying pipes on the lower end of the mixing compartment, and then the molten metal component is extruded by the screw extruding mechanism in each spray head to be scanned, printed and formed layer by layer. The 3D printing dispensing extruding device is reasonable in design and precise in dispensing and is suitable for online mixing and detection of multiple metal powder/particles, and the online alloying of 3D printer and the integrated formation of gradient material structural parts can be effectively achieved.