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Engineering Science and Materials Commons™
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- Additive manufacturing (2)
- Direct ink writing (2)
- Analytical model (1)
- Chemical initiation (1)
- Computational modeling (1)
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- Destructive testing (1)
- Epoxy (1)
- Extrusion (1)
- Extrusion compression molding (1)
- Filament winding (1)
- Friction stir welding (1)
- Interfacial stick-slip condition (1)
- Long fiber thermoplastic (1)
- Non-destructive testing (1)
- Polymer composites (1)
- Processing window (1)
- Rheology (1)
- Solid-state bonding (1)
- Structural stability (1)
- Thermoset polymers (1)
Articles 1 - 4 of 4
Full-Text Articles in Engineering Science and Materials
Innovations In Aligned And Overmolded Long Fiber Thermoplastic Composites, Shailesh P. Alwekar
Innovations In Aligned And Overmolded Long Fiber Thermoplastic Composites, Shailesh P. Alwekar
Doctoral Dissertations
Long fiber thermoplastic (LFT) composite materials are increasingly used in high performance lightweight automotive, sporting, and industrial applications. LFT composites are processed with extrusion-compression molding (ECM) and/or injection molding (IM). Melt extrusion offers unique opportunities to align long fibers in a thermoplastic polymer melt. The properties of LFT materials are highly influenced by processing techniques which leads to different porosity content, fiber length distribution, and fiber orientation distribution. Hence, it is important to understand the various LFT processing techniques and their effect on mechanical, thermal, and microscopic properties.
The fundamental process-property relationships in LFT composites are investigated in this dissertation. …
Structural Stability Of Thermosets During Material Extrusion Additive Manufacturing, Stian K. Romberg
Structural Stability Of Thermosets During Material Extrusion Additive Manufacturing, Stian K. Romberg
Doctoral Dissertations
Over the past decade, the scale of polymer additive manufacturing has been revolutionized with machines that print massive thermoplastic parts with greater geometric complexity than can be achieved by traditional manufacturing methods. However, the heat required to print thermoplastics consumes energy and induces thermal gradients that can reduce manufacturing flexibility and final mechanical properties. With the ability to be extruded at room temperature and excellent compatibility with fibers and fillers, thermoset resins show promise to decrease the energy consumption, expand the manufacturing flexibility, and broaden the material palette offered by large-scale polymer additive manufacturing. However, structural instability in the uncured …
Process-Structure-Property Relationships In 3d-Printed Epoxy Composites Produced Via Material Extrusion Additive Manufacturing, Nadim S. Hmeidat
Process-Structure-Property Relationships In 3d-Printed Epoxy Composites Produced Via Material Extrusion Additive Manufacturing, Nadim S. Hmeidat
Doctoral Dissertations
Extrusion-based additive manufacturing (AM) technologies, such as direct ink writing (DIW), offer unique opportunities to create composite materials and novel multi-material architectures that are not feasible using other AM technologies. DIW is a novel 3D-printing approach in which viscoelastic inks, with favorable rheological properties, are extruded through fine nozzles and patterned in a filament form at room temperature.
Recent developments in DIW of polymer composites have led to expanding the range of materials used for printing, as well as introducing novel deposition strategies to control filler orientation and create improved functional/structural composite materials. Despite these substantial advancements, the successful and …
Mechanics Of The Solid-State Bonding Under Severe Thermomechanical Processes, Xue Wang
Mechanics Of The Solid-State Bonding Under Severe Thermomechanical Processes, Xue Wang
Doctoral Dissertations
Friction stir welding (FSW) has found increased applications in automotive and aerospace industries due to its advantages of solid-state bonding, no fusion and melting, and versatility in various working conditions and material combinations. The extent and quality of the solid-state bonding between workpieces in FSW is the ultimate outcome of their industrial applications. However, the relationship among processing parameters, material properties, and bonding extent and fidelity remains largely empirical, primarily because of the lack of the mechanistic understanding of (1) tool-workpiece frictional behavior, and (2) bonding formation and evolution.
In this dissertation, to study the underlying mechanism of tool-workpiece frictional …