TY - JOUR
T1 - Development of a single loop EPR test method and its relation to grain boundary microchemistry for alloy 600
AU - Kain, Vivekanand
AU - Watanabe, Yutaka
N1 - Funding Information:
The authors thank Thomas Angeliu of CRD, General Electric, Schenectady for providing the heat-treated samples for this study. They are also thankful to him for useful discussions and suggestions during preparation of the manuscript. The support for a fellowship (P#98383) to one of the authors by the Japan Society for Promotion of Science (JSPS) is gratefully acknowledged.
PY - 2002/4
Y1 - 2002/4
N2 - A single loop electrochemical potentiokinetic reactivation test method has been developed for alloy 600 that produces good passivation on all the surfaces, good etching during the reactivation scan and no appreciable pitting. It is able to quantify and discriminate between samples with a wide range of degree of sensitization. The Pa value correlates well with the minimum level of chromium in the depletion regions at the grain boundaries. It has been shown that the width of the attacked regions is much larger than the width of chromium depletion regions and it does not show any direct correlation with either depth or width or with a volume parameter of chromium depletion regions. It has been shown that the chromium carbides are not attacked during the test and that the intragranular regions attacked during the test are the sites of chromium carbides in the grain matrix. A modified Pa parameter is shown to be sensitive down to 7.5 wt% chromium in the depletion regions and indicates that the intragranular carbides have shallower depletion profiles than those at grain boundaries. Comparison of the results of the single loop and the double loop tests showed a good correlation.
AB - A single loop electrochemical potentiokinetic reactivation test method has been developed for alloy 600 that produces good passivation on all the surfaces, good etching during the reactivation scan and no appreciable pitting. It is able to quantify and discriminate between samples with a wide range of degree of sensitization. The Pa value correlates well with the minimum level of chromium in the depletion regions at the grain boundaries. It has been shown that the width of the attacked regions is much larger than the width of chromium depletion regions and it does not show any direct correlation with either depth or width or with a volume parameter of chromium depletion regions. It has been shown that the chromium carbides are not attacked during the test and that the intragranular regions attacked during the test are the sites of chromium carbides in the grain matrix. A modified Pa parameter is shown to be sensitive down to 7.5 wt% chromium in the depletion regions and indicates that the intragranular carbides have shallower depletion profiles than those at grain boundaries. Comparison of the results of the single loop and the double loop tests showed a good correlation.
UR - http://www.scopus.com/inward/record.url?scp=0036531855&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0036531855&partnerID=8YFLogxK
U2 - 10.1016/S0022-3115(02)00712-2
DO - 10.1016/S0022-3115(02)00712-2
M3 - Article
AN - SCOPUS:0036531855
VL - 302
SP - 49
EP - 59
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
SN - 0022-3115
IS - 1
ER -