SUBJECT: Ph.D. Proposal Presentation
BY: Jonathan Holmes
TIME: Thursday, August 2, 2018, 9:00 a.m.
PLACE: MARC Building, 201
TITLE: Development of Novel Mixing Techniques for Material Extrusion Processes to Produce Functionally Graded Materials
COMMITTEE: Dr. David Rosen, Chair (ME)
Dr. Shreyes Melkote (ME)
Dr. Yan Wang (ME)
Dr. Meisha Shofner (MSE)
Dr. Jason Nadler (GTRI/MSE)


The proposed research envisions the creation of a novel mixing delivery system for filament fed systems that will add the capability of producing functionally graded material (FGM) to the material extrusion process. For the proposed research, mixing is achieved by leveraging the material extrusion process colloquially known as fused-deposition modeling or the FDM process. Through the material extrusion process, two or more materials can be combined in filament form, melted, and then mixed to create a heterogeneous material with a mixture of physical properties. This seemingly simple concept raises several technical challenges that will be explored as part of this research.

The proposed AM mixing solution requires controlling the deposition of mixed filament to produce usable FGM products. Two major research challenges arise when addressing this with a material extrusion based system. First, a mixing system must be designed to manage the variable properties created by combining material systems, primarily thermoplastics, with drastically different physical properties. A prototype mixing device has been fabricated and tested as part of this research. Second, a general process planning methodology must be created that manages the deposition scheme. Related research has addressed several of the process planning challenges, yet the unique system-level challenges of the proposed solution have yet to be demonstrated. The ultimate goal of this research is to pave the way for a new class of AM machines referred to as Mixing Material Extrusion (MME) Systems.