Design, Synthesis, and Tribological Evaluation of Polymeric-based Nanocomposites
Abstract
In the last decade, 3D printing has revolutionized the design and manufacturing industry. Stereolithography (SLA), the most accurate commercially-available form of 3D printing, and the third most commonly used 3D printing method, is used in diverse industries: from automotive to healthcare. One of the main limitations of the SLA process is the limited number of commercially-available high-performance resins. This is the problem that our research has aimed to address. The objective of this research was to design and synthesize a novel polymer-based 3D printable photoactivated nanocomposite that could be used to print parts with superior tribological capabilities. Layered zirconium hydrogen phosphate with α-type structure, Zr(HPOv4)v2.Hv2O, a low-cost environmental-friendly anti-wear & anti-friction additive, was chosen as the additive, and standard photoreactive clear resin was chosen as the polymer matrix. Specimens containing a series of concentrations from 0 to 1% (by weight) of α-ZrP nanoparticles were fabricated using two different approaches – casting & 3D printing. The fabricated specimens were subjected to wear & friction tests, using a pin-on-disc tribometer at room temperature. The worn surfaces were characterized using optical microscopy and interferometry.
Samples with 0.1 wt.% of α-ZrP nanoparticles showed promising results. 3D printed samples showed a 65% reduction in wear and a 34% reduction in friction. Similar to 3D printed samples, casted samples exhibited a 67% reduction in wear and a 32% reduction in friction. In comparison between the two fabrication processes, it was observed that 3D printing significantly improves the wear resistance of specimens. 3D printed specimens showed a 40% reduction in wear volume as compared to the casted specimens. This improved performance was attributed to the layer-by-layer printing approach employed in 3D printing, leading to more improved alignment of α-ZrP nanoparticles within each layer of the 3D printed specimens. The findings of this research are beneficial to the advanced manufacturing and polymer nanocomposite industry, and explore new areas for the application of nanoparticles in synthesizing superior polymer-based 3D-printable nanocomposites. The thesis consists of six chapters. Chapter I includes background information about stereolithography, tribology and polymer nanocomposites. Chapter II discusses the motivation and objectives. Chapter III discusses experimentation methodologies and materials used in this research. Chapter IV and V present and discuss the results obtained - casted versus 3D printed. Chapter VI provides a summary of the major conclusions obtained from the results, and recommends suggestions for future work.
Citation
Chakraborty, Sayak (2019). Design, Synthesis, and Tribological Evaluation of Polymeric-based Nanocomposites. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /195906.