Aerospace Propulsion and Power Materials and Structures Research at NASA Glenn Research Center

A comparative study on Cf/PyC/SiC minicomposites prepared via CVI process for hypersonic engine application

“…C f /PyC/SiC composites are primarily used as thermostructural materials under oxidizing environments. Evaluation of oxidation resistance of these materials is important, particularly when they are to be used as combustion chamber material for a hypersonic air breathing engine . As this study is part of the combustion chamber development activity, an initial comparative evaluation of oxidation resistance among the three composite systems is necessary.…”

“…Evaluation of oxidation resistance of these materials is important, particularly when they are to be used as combustion chamber material for a hypersonic air breathing engine. 4,34 As this study is part of the combustion chamber development activity, an initial comparative evaluation of oxidation resistance among the three composite systems is necessary. Among the three constituents in the current CMC system, the carbon fiber and the PyC interphase are the most oxidation prone parts.…”

Improved hyper-reduction approach for the forced vibration analysis of rotating components

“…Rotating components including turbine blades and propellers are efficient power delivery apparatus that are acted upon by unsteady aerodynamic forces. As a result of the rotation, the machinery suffers from various vibratory loads that may cause catastrophic failures such as high cycle fatigue (HCF) [1]. Therefore, the design process of the rotating components should include an investigation of their vibration characteristics.…”

In‐plane shear damage behaviours of 2D needled C/SiC composites

“…Carbon fibre‐reinforced silicon carbide matrix composites (C/SiC composites) are considered to be one of the most potential candidate materials for aerospace structures on account of their excellent thermal, physical, and mechanical performance at room and elevated temperatures . The advanced needling technology has been recognized as an economical and practical way to manufacture fibre preforms for C/SiC composites.…”

“…acoustic emission, C/SiC composites, digital image correlation, electrical resistivity, shear damage Nomenclature: DIC, digital image correlation; ER, electrical resistivity; AE, acoustic emission; CVI, chemical vapour infiltration; ROI, region of interest; τ xy , shear stress; P, applied shear load; A, minimum cross-sectional area of specimen; l, width across the notches; t, thickness at the notches; RSTD, relative standard deviation; γ xy , shear strain; γ max xy , maximum shear strain; γ min xy , minimum shear strain; γ N xy , normalized shear strain; n, number of shear strain points of specific strain field; i, index of the shear strain points; R, current resistance; R 0 , initial resistance; ΔR, resistance change 1 | INTRODUCTION Carbon fibre-reinforced silicon carbide matrix composites (C/SiC composites) are considered to be one of the most potential candidate materials for aerospace structures on account of their excellent thermal, physical, and mechanical performance at room and elevated temperatures. [1][2][3] The advanced needling technology has been recognized as an economical and practical way to manufacture fibre preforms for C/SiC composites. Besides, it is suitable for producing complex aerospace components [4][5][6] compared with other manufacturing techniques such as stitching, weaving, and braiding.…”