Method And Apparatus For Controlling Heat For Improved Extrudate Flow In Three-Dimensional (3D) Printing

A method of forming a metal part via additive manufacturing, the method comprising:

• receiving a solid rod of feedstock within an extruder;
• moving the feedstock gravitationally downward through the extruder from a proximal region of the extruder towards an extrusion tip while the feedstock is oriented along a longitudinal axis of the extruder that passes through the extrusion tip;
• cooling the proximal region of the extruder to maintain the feedstock as the solid rod while the feedstock is within the proximal region of the extruder;
• and
• heating the extrusion tip to at least partially melt the feedstock as it passes through the extrusion tip in order to extrude the at least partially melted feedstock from the extrusion tip;
• and
• extruding the at least partially melted feedstock from the extrusion tip to form the metal part.

A method of forming a metal part via additive manufacturing, the method comprising:

• receiving a solid rod of feedstock within an extruder, wherein the extruder includes a cooled proximal portion, a heated distal tip, and a longitudinal axis extending through a central region of the proximal portion and a central region of the distal tip;
• moving the feedstock through the proximal portion and towards the distal tip while the feedstock is oriented along the longitudinal axis;
• cooling the feedstock to maintain the feedstock as the solid rod while the feedstock is within the proximal portion so that the feedstock resists deformation while moving through the proximal portion;
• and
• heating a portion of the feedstock located within the distal tip to at least partially melt the feedstock as it passes through the distal tip in order to extrude the at least partially melted feedstock from the distal tip.

A system for forming a metal part via additive manufacturing, the system comprising:

• an extruder of a three-dimensional printer, the extruder having a cooled proximal portion, a heated distal tip, and a longitudinal axis extending through a central region of the proximal portion and a central region of the distal tip, wherein the extruder is configured to receive a feedstock in a solid form;
• a chamber housing at least the proximal portion of the extruder;
• a heat sink thermally coupled to the proximal portion of the extruder and configured to cool the proximal portion of the extruder;
• a heat block thermally coupled to the distal tip of the extruder and configured to heat the distal tip of the extruder;
• and
• a heat break located between the heat sink and the heat block, thermally separating the heat sink from the heat block.