Abstract
The ASTM A262 Practice A procedure is frequently used to assess whether Type 304/304L austenitic stainless steels are "sensitized". In this study, Type 304L steel containing 18 ppm boron examined in the as-received (mill solution-annealed) condition exhibited a "dual" structure after the Practice A test despite its low C content. Detailed characterization of this alloy was performed to assess the precipitation behavior in this steel. Intergranular, Cr-rich M2B- borides, identified by electron diffraction, were observed in the as-received condition. Samples aged at 700°C (nominally "sensitized") produced fully "ditched" grain boundaries having Cr levels in excess of 14 wt.% and concomitant Cr-depleted zones less than 50 nm in extent. Despite exhibiting fully "ditched" grain boundaries, Cr levels of ∼18-20 wt.% with no Cr-depleted zones were detected in specimens aged at 900°C (nominally "stabilized"). These results show the Practice A test can be mis-used/mis-interpreted for assessing sensitization.
| Original language | English |
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| Title of host publication | 15th International Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactors 2011|Int. Conf. Environ. Degrad. Mater. Nucl. Power Syst.-Water React. |
| Place of Publication | Warrendale, PA |
| Publisher | Minerals, Metals & Materials Society |
| Pages | 469-478 |
| Number of pages | 9 |
| Volume | 1 |
| ISBN (Print) | 9781622761944 |
| Publication status | Published - 2011 |
| Event | 15th International Symposium on Environmental Degradation of Materials in Nuclear Power Systems -- Water Reactors - Colorado Springs, CO Duration: 31 Jul 2011 → 5 Aug 2011 |
Conference
| Conference | 15th International Symposium on Environmental Degradation of Materials in Nuclear Power Systems -- Water Reactors |
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| City | Colorado Springs, CO |
| Period | 31/07/11 → 5/08/11 |