The Compaoparison of Characteristics of Fracture Toughness of Materials for Nuclear Piping by Use of Various Types of Specimens

Abstract:

Since it is difficult to cut off large specimens from nuclear piping, generally the standard CT specimens of 1T are used to perform fracture toughness tests. However, when compared with the test result obtained from a real pipe, the results from CT specimens are been known to be very conservative. Therefore, the U.S. Nuclear Regulatory Commission recommends the use of specimens whose thickness is greater than or equal to the thickness of a real pipe for estimating the stability of crack resistance[1]. In this study, a series of fracture toughness tests were performed using various types of specimens: the standard CT, non-standard Compact Pipe, and Curved CT. The results of the tests were compared.

• Periodical: Advanced Materials Research (Volumes 415-417)
• Pages: 2281-2287
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.415-417.2281
• Online since: December 2011
• Authors: Hui Hwan Kwon, Soo Park, Jae Min Koo, Chang Sung Seok
• Keywords: Compact Pipe, Compact Tension Specimen, Constraint Effect, Curved Compact Tension Specimen, Fracture Toughness Test, J-R Curve, Real Pipe

References

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