Community Research and Development Information Service - CORDIS

Abstract

Up to now 20 surveillance specimen sets of 14 VVER-1000 Reactor Pressure Vessel (RPV) have been evaluated in Russia, Ukraine and Bulgaria by different testing organizations:

-Kurchatov Institute, Russia- (10 RPVs).
-Institute for Nuclear Research, Ukraine- (2 RPVs).
-Institute of Metal Science, Bulgaria- (2 RPVs).

The extended analysis presented here is base on the results of 17 surveillance sets testing results of surveillance programmes. The materials involved contain very low and homogeneous levels of Phosphorus and Copper and a significant variation of Nickel and other elements like Manganese etc.

The observed temperature transition shifts are showing consistent behavior:
-The steels with low Nickel content are embrittling at a much lower rate than the one predicted by the Guide (chemistry factor = 20)
-The Guide looks to be conservative also for the higher Nickel steels if the content of Manganese is lower than 0.8 wt%.
-The steels embrittling at much higher rates are those with high Nickel and high Manganese contents at the same time.

The threshold for Nickel is evaluated to be at Ni>1.5 wt% and for Manganese at Mn > 0.8 wt%.

Manganese, together with Nickel, seems to playa key role in low Cu and p steels embrittlement.

Correlation analysis which considers Ni and Mn and fluence dependence to 113 power are showing predictive capabilities within 20 degrees Celsius scatter band in most cases.

Other elements, like for example Carbon and Sulphur could also explain the residual scatter in the data. atter in the data.

Additional information

Authors: KRYUKOV A, RRC-KI, Moscow (RU);ERAK D, RRC-KI, Moscow (RU);DEBARBERIS L, EC-JRC, Institute for Advance Materials, JRC-IAM, Petten (NL);SEVINI F, EC-JRC, Institute for Advance Materials, JRC-IAM, Petten (NL);ACOSTA B, EC-JRC, Institute for Advance Materials, JRC-IAM, Petten (NL)
Bibliographic Reference: An oral report given at: IAEA Experts Meeting . Sponsored by: IAEA. Held in: Gloucester, 14-17 May 2001
Record Number: 200013612 / Last updated on: 2001-07-30
Category: PUBLICATION
Original language: en
Available languages: en