Material deposition system for additive manufacturing

A material deposition system for additive manufacturing comprising:

• an extruder having:
• two or more input ports for receiving two or more feed materials,
• two or more liquefication passages, each of the two or more liquefication passages being associated with a respective one of the two or more input ports for receiving a respective one of the two or more feed materials,
• a mixing chamber downstream of the two or more liquefication passages for receiving the two or more feed materials from the two or more liquefication passages,
• a mixing device for mixing the two or more feed materials in the mixing chamber to create a blended deposition material, and
• an extrusion port for extruding the blended deposition material;
• two or more heating elements, each of the two or more heating elements being in thermal communication with a corresponding one of the two or more liquefication passages, the two or more heating elements each being configured to independently heat and liquefy the respective feed material upstream of the mixing chamber to thereby deliver the respective liquefied feed material downstream toward the mixing chamber for mixing thereof;
• a measuring device configured to measure the viscosity and/or other rheological properties of the blended deposition material in the mixing chamber;
• and
• a controller operatively coupled to the measuring device and operatively coupled to the two or more heating elements;
• wherein the controller is configured to receive information from the measuring device corresponding to the measured viscosity and/or other rheological properties of the blended deposition material in the mixing chamber;
• and
• wherein the controller is configured to adjust temperatures of the two or more heating elements independently of one another in response to the information received from the measuring device corresponding to the measured viscosity and/or other rheological properties of the blended deposition material in the mixing chamber.