Accession Number:

AD0745299

Title:

Damage-Function Analysis of Neutron Embrittlement in Steel at Reactor Service Temperatures

Descriptive Note:

Final rept.

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s):

• Serpan, Jr, Charles Z.

Report Date:

1972-06-01

Pagination or Media Count:

19.0

Abstract:

Neutron-induced increases in the brittle-ductile transition temperature delta TT of A302-B pressure vessel steel have been measured from irradiations in a number of reactor environments for neutraon fluences representative of pressure vessel design lifetimes. While these measurements have permitted formulation of the trends necessary for delta TT projections in operating reactors, certain anomalous results have been observed wherein measurements fell outside the nominal limits of the trends. As a summation of research on this steel and to resolve the anomalous results, a damage function was derived for the neutron-induced delta TT response of A302-B steel at reactor operating temperatures. The damage function is a series of weighting factors for the damaging capacity of neutrons of all energy groups in a reactor spectrum these factors thus indicate the relative importance of specific energy-group neturons to the damaging process. Techniques for derivation of the damage function and the complementing correlation-evaluation method are directly applicable to more advanced reactor systems.

Descriptors:

• *DAMAGE
• *PRESSURE VESSELS
• LIFE EXPECTANCY(SERVICE LIFE)
• REACTOR MATERIALS
• THERMAL NEUTRONS
• NEUTRON REACTIONS
• STEEL
• TRANSITION TEMPERATURE

Subject Categories:

• Metallurgy and Metallography
• Radioactivity, Radioactive Wastes and Fission Products
• Fission Reactor Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE