The corrosion product of Cs–Te corrosive compound with 11Cr-Ferritic/Martensitic Steel and 9Cr-Oxide Dispersion Strengthened steel

Cs–Te corrosion depth dependence on distribution of chromium carbide precipitation in high chromium steel

“…Corrosion products in both specimens after the test were specified as Cr 3 Te 4 . Therefore Te Cr Cr Te → + can be presumable corrosion reactions the same as previously reported reactions [10].…”

“…Stronger detection of Cr, Cs and Te from corroded areas and weaker detection of Cr in the vicinity of the corroded areas can be seen in both EDS mapping images ( Figure 6 (a)) and EDS line profiles ( Figure 6 (b)). The observation result corresponds to typical Cs-Te corrosion [10,15]. Cs and Te detections on the 9Cr-0.1C(A) surface are from the Cs-Te corrosive compound adhered during the corrosion test.…”

“…Energy value of a Te peak (Lβ2: 4.301 keV) is near a Cs peak (Lα1: 4.286 keV) which should be noted in this regard. As a result, the corrosion products both A and B can be specified as Cr 3 Te 4 , and the result corresponds to assumable corrosion reactions shown below according to a past reference [10]. Figure 9 shows histograms of corrosion extension depth in 9Cr-0.1C(A) and (B).…”

“…Main causative agents of FCCI in oxide fuel pin were estimated to be Cs and Te based on thermodynamic consideration by Adamson [9]. In addition, a past experimental report suggested that decomposition of chromium carbide at grain boundary by tellurium in cesium telluride can advance the Cs-Te corrosion in high chromium steel [10]. In an attempt to investigate Cs-Te corrosion depth dependence on distribution of chromium carbide precipitation in high chromium steel, Cs-Te corrosion out-pile tests of two 9Cr steels with different distributions of chromium carbide were carried out.…”