METHOD OF PRINTING SEMI-CRYSTALLINE MATERIALS UTILIZING EXTRUSION BASED ADDITIVE MANUFACTURING SYSTEM

摘要

A method of 3D printing a part with an extrusion-based additive manufacturing system includes providing a filament having a semi-crystalline material as a majority component of a polymeric matrix to a liquefier having a liquefier tube having an overall length between an inlet end and an outlet end. An upper portion of the liquefier tube adjacent the inlet end has a first length and a first cross-sectional area substantially perpendicular to a longitudinal axis and a lower portion of the liquefier tube adjacent the outlet end has a second length and a second cross-sectional area substantially perpendicular to the longitudinal axis, wherein the first cross-sectional area is greater than the second cross-sectional area. The method includes driving the filament into a melt zone located within the upper portion of the liquefier tube at a selected rate based upon a desired extrusion rate. The filament is melted within the melt zone forming a melt pool in the liquefier tube to provide the selected extrusion rate. The part is printed in a series of layers by extruding the melted filament having a majority of semi-crystalline material along tool paths representative of the part.