Accession Number:

ADA609952

Title:

National Hypersonic Science Center for Materials and Structures

Descriptive Note:

Final rept. 1 Jun 2009-31 Aug 2014

Corporate Author:

TELEDYNE SCIENTIFIC COMPANY THOUSAND OAKS CA

Report Date:

2014-08-31

Pagination or Media Count:

61.0

Abstract:

Research performed under the National Hypersonic Science Center for Materials and Structures NHSC-MS aimed to advance the basic science needed to guide design of new high-temperature oxidation-resistant ceramic materials and to develop characterization and analysis tools that enable life prediction for fiber-reinforced composites with geometrically complex microstructures. Highlights of the research are as follows The roles of transition element dopants in affecting oxidation resistance of ZrB2 ultra-high temperature ceramics, through the effects of the dopants on sintering andor stability of the oxidation products ZrO2, B-O glasses, and B-Si-O glasses, were elucidated through experiments and atomistic calculations. Structure, oxidation behavior, and stability of HfSiCNO ceramics were determined by experiment and atomistic calculations. The potential for beneficial oxidation reactions to form self-healing layers containing compounds that are resistant to water vapor erosion was explored. Two new experimental methods were developed for characterizing fiber architectures in ceramic matrix composites and observingmeasuring the evolution of damage under load at high temperatures, above 1500 deg C. One method uses digital surface image correlation and the other uses synchrotron x-ray micro tomography, which is capable of micron-scale resolution in 3-dimensional images. Under the umbrella of a virtual test system, methods were developed for i analyzing 3-dimensional images of microstructures of fiber reinforced composites to create statistical characterization of the microstructure, ii formulation of a probabilistic generator for creating virtual specimens that replicate the measured statistics, and iii creation of a computational model for a virtual specimen that allows representation of discrete damage events.

Subject Categories:

  • Ceramics, Refractories and Glass
  • Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE