Date on Master's Thesis/Doctoral Dissertation


Document Type

Master's Thesis

Degree Name

M. Eng.


Mechanical Engineering

Degree Program

Mechanical Engineering, MS

Committee Chair

Kate, Kunal

Committee Co-Chair (if applicable)

Bhatia, Bikram

Committee Member

Bhatia, Bikram

Committee Member

Satyavolu, Jagannadh

Author's Keywords

sizing agents; filament extrusion; acrylonitrile butadiene styrene; carbon fiber–polymer composites; fused filament fabrication; additive manufacturing


This study demonstrated the effects of changing the sizing agent parameter during the preparation of carbon fibers on the mechanical properties of composite made with acrylonitrile butadiene styrene (ABS) as the matrix material and carbon fibers as the fiber material. Three types of sizing agents produced by Allnex were used to coat three different batches of carbon fibers that were mixed with a torque rheometer and extruded with a barrel-style melt extruder into continuous spools of 1.75 mm filament for use with commercial 3D printers. Tensile tests were conducted on the filaments and tensile bars printed from the materials. Results showed that mechanical properties improved for each sizing agent when compared to nominal properties for ABS, but when compared to previously studied properties for fibers sized with an epoxy-based agent, modulus was not as high but tensile stress was around the same. This indicated that the physical limitation of the properties of the tensile strength of the fibers is independent of sizing agent chosen, but tensile modulus changed accordingly with the sizing agent chosen. Further studies should be done to document effects of a wider library of sizing agents on the mechanical properties of carbon fiber composites.