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Full-Text Articles in Engineering
Creep Of Nextel 720/Alumina Ceramic Matrix Composite With Diamond-Drilled Effusion Holes At 1200°C In Air And In Steam, Megan L. Harkins
Creep Of Nextel 720/Alumina Ceramic Matrix Composite With Diamond-Drilled Effusion Holes At 1200°C In Air And In Steam, Megan L. Harkins
Theses and Dissertations
A recent study evaluated tensile stress-strain and tensile creep behavior of an oxide-oxide composite (Nextel™720/alumina) with laser-drilled effusion holes at 1200°C. It was determined that the presence of laser-drilled holes degraded the mechanical properties and performance of the CMC as a result of damage caused to the composite microstructure by the laser drilling process. Based on these results, the present effort sought to assess the effects of diamond-drilled holes on the mechanical behavior of this CMC. Tensile properties of the N720/A composite at 1200°C in laboratory air were unaffected by the presence of an array of 17 diamond-drilled effusion holes. …
Interlaminar Shear Performance Of High Temperature Composites, Tyler A. Wallis
Interlaminar Shear Performance Of High Temperature Composites, Tyler A. Wallis
Theses and Dissertations
Interlaminar shear properties of a high temperature polymer matrix composite (HTPMC) and a ceramic matrix composite (CMC) were evaluated at elevated tempera- ture. Two variants of the HTPMC were studied. Both consisted of a high-temperature polyimide (AFR-PE-4) matrix reinforced with Astroquartz-III pre-impregnated glass fabric woven in an eight-harness-satin weave. The first HTPMC variant also contained stainless steel foil at the midplane, while the second HTPMC variant did not. The interlaminar shear strength (ILSS) of both variants of the HTPMC was evaluated at 204°C in laboratory air. The addition of the stainless steel foil resulted in significant loss of ILSS for …
Creep Of Hi-Nicalon™ S Ceramic Fiber Tows At 700°C In Air And In Silicic Acid-Saturated Steam, Matthew W. Piper
Creep Of Hi-Nicalon™ S Ceramic Fiber Tows At 700°C In Air And In Silicic Acid-Saturated Steam, Matthew W. Piper
Theses and Dissertations
Aircraft structural and engine components are subjected to elevated temperature and steam environments during operation. Turbine blades experience particularly harsh conditions that are approaching the operating temperature limits of current Nickel-based superalloys even with active cooling. Ceramic matrix composites (CMCs), which demonstrate high specific strength and specific stiffness and maintain these properties at elevated temperatures such that active cooling is not required, are prime candidates to replace superalloys as the materials for turbine blades. Ceramic matrix composites are composite materials that consist of a ceramic matrix with fiber reinforcement. This research investigated a silicon carbide (SiC) fiber, Hi-Nicalon™ S, which …