Processing and mechanical behavior of Nicalon{reg_sign}/SiC composites with sol-gel derived oxide interfacial coatings

Technical Report · Tue Oct 01 04:00:00 EDT 1996

DOI:https://doi.org/10.2172/458590· OSTI ID:458590

Shanmugham, S; Liaw, P K ^[1]

---

1. Tennessee Univ., Knoxville, TN (United States). Dept. of Materials Science and Engineering

Recent analytical and finite element modeling studies have indicated that low modulus interface materials are desirable for obtaining Nicalon/SiC composites with good toughness. Two oxides, Al titanate and mullite, were chosen on this basis as interface materials. The oxide and C coatings were deposited by sol-gel and CVD, respectively. Nicalon/SiC composites with oxide/C and C/oxide/C interfaces were fabricated and evaluated for flexure strength in the as-processed and oxidized conditions. Composites with C/oxide/C interfaces retained considerable strength and damage-tolerant behavior even after 500 h oxidation at 1000 C in air. The C/oxide/C interface shows promise as a viable oxidation-resistant interface alternative to C or BN interfaces.

• Research Organization: Oak Ridge National Lab., TN (United States); Tennessee Univ., Knoxville, TN (United States). Dept. of Materials Science and Engineering
• Sponsoring Organization: USDOE Assistant Secretary for Fossil Energy, Washington, DC (United States)
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 458590
• Report Number(s): ORNL/Sub--95-99732/01; ON: DE97051267
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COATINGS
COMPOSITE MATERIALS
FIBERS
FLEXURAL STRENGTH
INTERFACES
OXIDATION
SILICON CARBIDES