Effects of high-temperature environments on flaw generation and fracture behavior of SiC/SiC composites

Technical Report · Wed Feb 01 04:00:00 EST 1995

DOI:https://doi.org/10.2172/28388· OSTI ID:28388

Singh, J P; Singh, D ^[1]

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1. Argonne National Lab., IL (United States). Energy Technology Div.

Flaw generation and fracture behavior of Nicalon-fiber-reinforced SiC matrix composites are influenced by high temperatures. Therefore, the authors evaluated the effects of temperature by measuring the strength of these composites at several temperatures ranging from 800 to 1,300 C, and by characterizing their microstructure. While composite strength increased from {approx}400 MPa at room temperature to {approx}532 MPa at 800 C, it decreased to {approx}270 MPa at 1,300 C. Such degradation of composite strength at high temperature is believed to be partly due to fiber degradation. In-situ fiber strength of composites tested at room and elevated temperatures was estimated by fractographic techniques. The in-situ strength of fibers in composites was significantly lower than that of as-received fibers. This decrease is believed to be related to flaws that develop during processing and to exposure to elevated-temperature service environments.

• Research Organization: Argonne National Lab., IL (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 28388
• Report Number(s): ANL/ET/CP--83155; CONF-950245--1; ON: DE95008270
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
EXPERIMENTAL DATA
FRACTURE PROPERTIES
HEAT RESISTANT MATERIALS
MICROSTRUCTURE
SILICON CARBIDES
TEMPERATURE DEPENDENCE