Abstract

Mechanical characterization of both the bulk and individual layer properties of layered polymer stacks provides important information for their use in novel applications. A single technique to measure both the bulk and layer properties is atempted. Ultrasonic testing provides an opportunity to determine the mechanical characteristics for layered samples in the form of the complex mechanical moduli. These moduli express the viscoelastic properties of the materials. Using ultrasound, this can be done for the bulk and the layers in a single test. With ultrasound, the ability to determine the complex moduli in single layers has been demonstrated. The moduli were determined within the expected range. The ultrasonic testing has also allowed the determination of the speed of sound of the individual layers in a 2 layer sample consisting of layers of Polycarbonate and Poly(methyl methacrylate). Internal interference limited the ability to measure attenuation. To attempt to allow for analysis of these complex waveforms, a secondary technique for waveform analysis has been proposed and developed. This method employs a finite element simulation to replicate the experiment. By deriving a simulation with the complex moduli as inputs, it is possible to use the simulation results to measure the moduli of multilayered samples. This is done comparatively through iteration of the simulation inputs. When a set of inputs creates a simulated result matching the experimental scans, a solution has been found. A preliminary version of the simulation is presented and demonstrated.

Library of Congress Subject Headings

Polymers--Mechanical properties--Research; Polymeric composites; Viscoelastic materials; Ultrasonic testing

Publication Date

2010

Document Type

Thesis

Department, Program, or Center

Mechanical Engineering (KGCOE)

Advisor

Varela, B.

Advisor/Committee Member

Helguera, Maria

Advisor/Committee Member

Jamdamba, B.

Comments

Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: TA418.9.C6 F47 2010

Campus

RIT – Main Campus

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