Fused deposition modeling with localized pre-deposition heating using forced air

Abstract

Rapid prototyping (RP) systems have been used for several years to produce design prototypes without expensive tooling costs. As these systems have matured, there has been increasing interest in using them to produce actual end-use parts. Fused deposition modeling (FDM) is an RP technology that has been identified by many as having strong potential for this transition from rapid prototyping to rapid manufacturing, due primarily to its capability of using a wide array of high performance materials. FDM creates parts layer-by-layer, extruding semi-molten material "roads" through a computer-controlled nozzle onto the substrate, which is mounted on an indexing platform. This manufacturing process creates anisotropic parts, with strength properties greater along material roads than across roads or between layers.

This study proposes to improve FDM part strength in the transverse directions by increasing the amount of material bonding taking place between road and layers through the addition of a system which re-heats the substrate material immediately preceding deposition. To test this concept, a simple pre-deposition heating system (PDHS) was designed, implemented, and tested, measuring part properties in the axial and transverse directions and part dimensional accuracy. The test results were analyzed using statistical techniques, and found that parts made with the PDHS were not significantly stronger in the transverse direction than parts made without the PDHS. The development of the system and test results illustrate the challenges of implementing a PDHS system and lead to a set of recommendations for the next design iteration of PDHS.