Methods for the In-Situ Characterization of Cast Austenitic Stainless Steel Microstructures

Conference · Wed Jun 29 04:00:00 EDT 2011

DOI:https://doi.org/10.1063/1.3592057· OSTI ID:1023199

Ramuhalli, Pradeep; Good, Morris S; Harris, Robert V; Bond, Leonard J; Ruud, Clayton O; Diaz, Aaron A; Anderson, Michael T

Cast austenitic stainless steel (CASS) that was commonly used in U.S. nuclear power plants is a coarse-grained, elastically anisotropic material. Its engineering properties made it a material of choice for selected designs of nuclear power reactor systems. However, the fabrication processes result in a variety of coarse-grain microstructures that make current ultrasonic in-service inspection of components quite challenging. To address inspection needs, new ultrasonic inspection approaches are being sought. However, overcoming the deleterious and variable effects of the microstructure on the interrogating ultrasonic beam may require knowledge of the microstructure, for potential optimization of inspection parameters to enhance the probability of detection (POD). The ability to classify microstructure type (e.g. polycrystalline or columnar) has the potential to guide selection of optimal NDE approaches. This paper discusses the application of ultrasonic and electromagnetic methods for classifying CASS microstructures, when making measurements from the outside surface of the component. Results to date demonstrate the potential of these measurements to discriminate between two consistent microstructures - equiaxed-grain material versus columnar-grain material. The potential for fusion of ultrasonic and electromagnetic measurements for in-situ microstructure characterization in CASS materials will be explored.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1023199
• Report Number(s): PNNL-SA-75073; 401001060
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
36 MATERIALS SCIENCE
Attenuation
Backscattering
CASS
DETECTION
EVALUATION
FABRICATION
IN-SERVICE INSPECTION
MICROSTRUCTURE
Microstructure Characterization
NUCLEAR POWER
NUCLEAR POWER PLANTS
OPTIMIZATION
PROBABILITY
STAINLESS STEELS
ULTRASONIC WAVES
Ultrasonic NDE