Experimental Plan and Irradiation Target Design for FeCrAl Embrittlement Screening Tests Conducted Using the High Flux Isotope Reactor

Database on Performance of Neutron Irradiated FeCrAl Alloys

“…Generation I alloys are ORNL developed model FeCrAl alloys with Y additions used to screen primary composition effects (Cr and Al) on radiation tolerance, as well as other key performance aspects such as welding [21], oxidation [4,9,22], burst behavior [23], and corrosion [24]. Generation I alloys are otherwise referenced as B-series alloys or model alloys in previous reports [3,[5][6][7][8][9][10][11][12][13][14][15][16]. Generation II alloys are ORNL developed FeCrAl alloys with Y additions that also include additional minor alloying elements such as Mo, Nb, Si, and/or C. Minor alloy additions and further refinement in thermomechanical processing for Generation II alloys means generally a higher strength alloy at elevated temperatures compared to Generation I alloys with identical or similar Cr and/or Al contents [3].…”

“…Phase I was based around exploratory studies of the Fe-Cr-Al design space and focused primarily on assessment of how various aspects of alloy performance were affected by major alloying element composition. The alloys utilized for these investigations were simple FeCrAl-Y model alloys and are typically regarded as Generation I FeCrAl alloys within reporting [3,[5][6][7][8][9][10][11][12][13][14][15][16]. These Phase I alloys have demonstrated that higher Cr and Al contents are generally more desirable for maximizing corrosion and/or oxidation resistance but too much of either can limit alloy applications; excessive Cr additions increase the formation of embrittling Cr-rich αʹ precipitates [17][18][19], while high Al content results in failure during the seamless tube extrusion process required for LWR cladding fabrication [20].…”

“…Computational thermodynamics models were utilized to guide minor alloying additions in order to enhance material strength while maintaining adequate high temperature oxidation resistance and good fabricability for thin-walled tube extrusion by commercial manufacturers. Summaries of the Generation II ATF FeCrAl alloys down-selection and design process can be found in previously published reports [3,[5][6][7][8][9][10][11][12][13][14][15][16]. These engineering alloys are currently undergoing irradiation in the High Flux Isotope Reactor (HFIR) at ORNL, with a subset of low-fluence specimens recently becoming available for analysis.…”

Evaluation on the Effect of Composition on Radiation Hardening and Embrittlement in Model FeCrAl Alloys

“…To overcome this deficiency and eliminate ambiguity in the analysis in Section 5, a series of irradiation campaigns have been initiated to specifically irradiate fracture toughness samples of varying FeCrAl composition. The full details on this irradiation program have been reported previously [47]. To summarize, an irradiation capsule has been designed to be irradiated in the HFIR at three different irradiation temperatures and two different damage doses.…”

“…Extensive PIE will be conducted including determination of the ΔT o values for the irradiated alloys as well as microstructural features contributing to any detected changes in the fracture toughness of the alloys. For further information, the reader is referred to the report published by Field et al [47].…”