The microstructural and microchemical examination of reactor pressure vessel steels

Conference · Thu Dec 31 04:00:00 EST 1992

OSTI ID:48029

Phythian, W J; English, C A ^[1]; Buswell, J T ^[2]

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1. Harwell Lab., Oxfordshire (United Kingdom)
2. Berkeley Nuclear Labs., Gloucestershire (United Kingdom)

The approach generally adopted to characterise the embrittlement of thermal reactor pressure vessels (RPV`s) is based on extensive mechanical testing. To understand the micro-structural and micro-chemical changes responsible for this behaviour requires a well coordinated multidisciplinary programme capable of correlating microstructural and mechanical properties changes. Application of advanced analytical techniques to measure directly critical parameters such as the matrix copper and the degree of copper precipitation in archive, surveillance and decommissioned plant material, have proved invaluable in embrittlement model validation and refinement. Information on the start of life copper availability, the degree of embrittlement incurred and the assessment of the potential for further embrittlement can be directly obtained from small samples milled or trepanned from operating RPV`s. Such information is critical to both operational safety and any plant life extension programme. This paper will review the critical issues, the techniques available to address them and the contributions these techniques have made to the understanding, and prediction, of embrittlement. Examples will be given from studies of copper precipitation, although the techniques and methodology employed would apply equally well to other aspects of the embrittlement process as will be discussed.

• OSTI ID: 48029
• Report Number(s): CONF-910808--
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
36 MATERIALS SCIENCE
EMBRITTLEMENT
INSPECTION
MECHANICAL PROPERTIES
RADIATION HARDENING
REACTOR VESSELS