Stochastic Modeling of Composite Reinforcement Fabrics
Carbon reinforced silicon carbide (C/SiC) and silicon carbide reinforced silicon carbide (SiC/SiC) are candidate materials for use in extreme conditions where temperatures in the range 2000 to 2800 °F are expected. The service life of ceramic matrix composites is limited due to degradation mechanisms that include oxidation, creep, fatigue, and damage. This research effort focuses on the effect of variation in the architecture characteristics of woven fabrics as a source of variation in durability of ceramic matrix composites. Properties and geometric characteristics of ceramic reinforcement fabrics are known to vary, but very little is known about the magnitude of variation. This research effort is developing a physics-based, stochastic, hierarchical textile model of the topology of woven fabrics. The technical approach is minimization of strain energy in bending in the woven fabric’s representative volume element, and the goal is to develop a preprocessor for finite-element based durability models. This research program is funded by NASA.

Damage Modeling and Reliability of Ceramic Matrix Composites
Many crack models currently in use are 2-D models of material behavior. Unfortunately, materials response in application is three-dimensional. The purpose of this project is to modify 2-D crack growth models to simulate 3-D failure in ceramic matrix composites. This research is an opportunity for a graduate student with a background in materials science, engineering mechanics, and computational techniques.

Application of Monte Carlo Modeling to Engineering Systems
Monte Carlo models are the combination of stochastic characteristics of engineering systems and deterministic models of system behavior. Relatively complex can be conveniently modeled by Monte Carlo methods, and both typical and unique system behaviors can be predicted. This research is an excellent opportunity for a graduate student with a background in materials science, applied statistics, and computational techniques.

Most Recent Works

“Stochastic Topology Model of Reinforcement Fabrics in Ceramic Matrix Composites,” D. N. Coon, in press, JANNAF Journal, 2009.
“Stochastic Model of Crack Paths in Woven Ceramic Matrix Composites,” D. N. Coon, Journal of Materials Science, 42 (1), 2007, p. 66.
“Numerical Simulation of Creep failure of a SiC Fiber Tow,” F. M. MacDonald, D. N. Coon, J. of Mat. Sci. and Tech., 12[1] 3-14 (2004).
"Monte Carlo Simulation of Creep Crack Growth in a 0°/90° Plain Weave SiC Composite," D. N. Coon, Journal of Materials Science, 38, 2003, p. 3121-3129.
"Mirror/Mist Radius Constant for Y-Al-Si-O-N Glass," Dennis N. Coon, Journal of Materials Science Letters, 21, p. 1121, 2002.
"Simulation of Creep Crack Growth in Ceramic Composites," P. Sodanapalli and D. N. Coon, Journal of Materials Science, 37, p. 4197, 2002.
"Monte Carlo Simulation of Fatigue of a Fiber Tow Undergoing Chemical Reaction," D. N. Coon an A. M. Calomino, Journal of Materials Science, 36, pp. 2597-2605, 2001.
"Numerical Investigation of the Effect of Variation of Fiber characteristics on the Reliability of Fibers in a Uniaxially Loaded Tow," D. N. Coon, Journal of Materials Science and Technology, 9(2), pp. 3-14, 2001.
"Monte Carlo Simulation of the Effect of Fiber Characteristics on the Steady State Creep Performance of a Fiber Tow," F. MacDonald and D. N. Coon, Journal of Materials Science, 36, pp. 1681-1684, 2001.
"Temperature Dependence of Strength and Fracture Toughness of Y-Al-Si-O-N Glass," Dennis N. Coon, Journal of Materials Science Letters, 20, pp. 751-752, 2001.
"Simulation of Composite Fatigue Resulting from Chemical Attack of Bridging Fibers," D. N. Coon and A. Motkur, Journal of Materials Science, 35, pp. 3207-3214, 2000.

Education
B.S. Ceramic Engineering, New York State College of Ceramics at Alfred Univ., 1980
M.S. Ceramic Science, Pennsylvania State University, 1984
PhD Ceramic Science, Pennsylvania State University, 1986