Investigation of the Microstructure Factors Affecting the Brittle Fracture Initiation of Pre-Cracked Charpy-Type Samples of VVER-1000 RPV Steel

Abstract:

The correlation between fracture toughness parameter K_Jc and cleavage initiation distance (CID) for the three point bending (3PB) pre-crecked Charpy type specimens of VVER-1000 reactor pressure vessel base and weld metals was observed. Two types of brittle fracture origin sites were found: nonmetallic inclusions and grain or subgrain boundaries. It was shown that K_Jc values are shifted to the higher temperature area for weld metal with respect to base metal data. In case when the initiation origin is grain or subgrain boundary, the K_Jc values are higher for base metal at the same CID values. This indicates the higher crack resistance of base metal.

• Periodical: Key Engineering Materials (Volumes 592-593)
• Pages: 635-638
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.592-593.635
• Online since: November 2013
• Authors: Evgenia A. Kuleshova, Maxim A. Artamonov, Artem D. Erak
• Keywords: Brittle Fracture, Cleavage Initiation Distance (CID), Critical Stress Intensity Factory K_jc, Fracture Toughness, Origin, Reactor Pressure Vessel Steel

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