This thesis discusses the effect of cryogenic temperatures on composite materials. The work includes estimating the shear strength of carbon/epoxy and glass/polyester composites at low temperatures and finding the rate of generation of microcracks in composites at cryogenic temperatures by acoustic emission technique. Microcracks increase the permeability of composites. So to study the permeability growth with microcracks, equipment is also designed to measure the permeability of composite to low temperature fluids. With short beam shear testing it was observed that the shear strength of composites increases with decreasing temperatures. Also carbon/epoxy composites were found to be much stronger than glass/polyester composites. Cryogenic temperatures improve the strength of composites but also generate microcracks in the structure due to the thermal expansion mismatch between the matrix and fiber. With acoustic emission testing from room to –150ºC, it was found that the rate of generation of microcracks increases with reducing temperatures. The work is extended to design a permeability equipment.

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Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 262-288). Also available in electronic version.

Electromagnetic shielding materials for plastic packaging in laser modules application were studied experimentally. Bipheny1, Nylon and LCP mixed with Al-powder, Al-flake, carbon-fibers and steel-fibers was fabricated and measured in shielding effectiveness(SE) for EMI. Compression molding, double-screw extrusion and injection molding were used for fabrication. We examed the mechanical properties and shielding effectiveness of these compounds. The SE of conductive plastics was measured to be 40dB at 30MHz and 60dB at 1GHz for carbon-fiber and plastic mixture. The experiment result indicates that introducting conductive carbon fiber fillers into plastics will produce conductive composites having an excellent SE to reduce EMI. With these excellent SEs, such conductive carbon fiber fillers into plastics are suitable for use in low-cost laser modules.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains iv, 87 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 83-86).

Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2004. / Dr. Zureick, Abdul-Hamid, Committee Member; Dr. White, Donald, Committee Member; Dr. Saxena, Ashok, Committee Member; Dr. Jacobs, Laurence, Committee Member; Dr. Haj-Ali, Rami, Committee Chair; Dr. Armanios, Erian, Committee Member. Vita. Includes bibliographical references (leaves 164-172).

Lic.-avh. Luleå : Luleå tekniska universitet, 2009.

Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 132-137). Also available in electronic version. Access restricted to campus users.

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xiv, 180 p. : ill. Includes abstract. Includes bibliographical references (p. 115-118).