Additive manufacturing with heat-flexed material feeding

A method of additive manufacturing, comprising:

• maintaining a first spool of a build material filament in a chamber, the build material filament comprising a matrix including one or more binder components and more than 50% by volume of sinterable powdered metal;
• maintaining a second spool of a release material filament in the chamber, the release material filament comprising a second binder and a powdered ceramic;
• dropping the build material filament over a drop height in the chamber from the first spool to a print head assembly;
• dropping the release material filament over the drop height from the second spool to the print head assembly;
• directly heating, with heated air from a heater in the chamber, the build material filament on the first spool and along the drop height to a temperature lower than a glass transition temperature of a softening component of the one or more binder components to flex the build material filament;
• depositing layers of the build material filament and the release material filament above a build plate, the drop height being substantially equal to or longer than a diagonal of the build plate;
• debinding at least one of the one or more binder components in the matrix and the second binder with a solvent to form a brown part assembly including each of the build material filament and the release material filament;
• and
• sintering the brown part assembly while decomposing the release material to a release powder.