Measurement of ultrasonic properties of ceramic/ceramic composite materials

Technical Report · Sat Feb 28 23:00:00 EST 1987

OSTI ID:6543549

Walter, J B; Lott, L A

Ceramic composites are an important new type of material being developed for applications requiring high strength at high temperatures. Considered here are composites of a SiC fabric reinforced SiC matrix formed by chemical vapor infiltration. An important aspect of this process is the formation of extensive porosity which is known to limit the strength of the material. Effective methods of nondestructively detecting and characterizing porosity in the material are needed. This is a challenging task for ultrasonics because of the high levels of porosity (typically 10 to 50%) found in the material and because of the intrinsic heterogeneity and anisotropy of the material, all of which strongly affect ultrasonic wave propagation. Techniques are described for measuring ultrasonic attenuation, transmitted energy, and propagation velocity using through-transmission. Measurements are included for a set of samples containing a range of porosity. It is concluded that the techniques are adequate to form a technical basis for developing effective ultrasonic NDE methods.

• Research Organization: EG and G Idaho, Inc., Idaho Falls (USA)
• DOE Contract Number: AC07-76ID01570
• OSTI ID: 6543549
• Report Number(s): EGG-SD-7621; ON: DE87009721
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
42 ENGINEERING
420500 -- Engineering-- Materials Testing
ACOUSTIC TESTING
CARBIDES
CARBON COMPOUNDS
COMPOSITE MATERIALS
MATERIALS
MATERIALS TESTING
NONDESTRUCTIVE TESTING
POROSITY
REINFORCED MATERIALS
SILICON CARBIDES
SILICON COMPOUNDS
TESTING
ULTRASONIC TESTING