Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56 Page 57 Page 58 Page 59 Page 60 Page 61 Page 62 Page 63 Page 64 Page 65 Page 66 Page 67 Page 68 Page 69 Page 70 Page 71 Page 72 Page 73 Page 74 Page 75 Page 76 Page 77 Page 78 Page 79 Page 80 Page 81 Page 82 Page 83 Page 84 Page 85 Page 86 Page 87 Page 88 Page 89 Page 90 Page 91 Page 92 Page 93 Page 94 Page 95 Page 96 Page 97 Page 98 Page 99 Page 100 Page 101 Page 102 Page 103 Page 104 Page 105 Page 106 Page 107 Page 108 Page 109 Page 110 Page 111 Page 112 Page 113 Page 114 Page 115 Page 116 Page 117 Page 118 Page 119 Page 120 Page 121 Page 122 Page 123 Page 124Nuclear Science User Facilities 114 It was noted byAECL following scanning electron microscope fractography studies that there was a definite difference in ductility (Figure 2) between the hot region of the spring and the cold region of the spring with the hotter, 12 o’clock region exhibiting brittle fracture features at lower DPA levels.Additionally, at higher DPA and He content there was no difference due to temperature (Figure 3). In correlation with this theTEM studies performed during 2012 and 2013 show a difference in cavity/bubble characteris- tics between high and low-temperature regions as well as cavity/bubble coales- cence at higher DPA levels (Figure 4). During FiscalYears 2014 and 2015, addi- tional material was shipped from Chalk River Laboratories to the INL EML to allow additional focus on helium bubble formation at grain boundaries in some of the more highly damaged regions of the garter springs. Sixteen additionalTEM lamellae were fabricated using the active FIB at INL and have been partially examined at CAES and McMaster University. FY 2015 marks the comple- tion of this project scope, but additional work scope may be pursued in aWork For Others agreement between Canadian Nuclear Laboratories and INL. Future Activities The NSUF portion of this project was completed in FY 2015.Additional studies will be carried out at McMaster University and at Canadian Nuclear Laboratories (CNL). Continued collaboration between CNL and INL is expected with a focus on the contribu- tion of helium formation to embrittle- ment of these springs.There are papers being drafted for submission including the work performed this fiscal year, which will likely be published in 2016, including authorship of INL’s Jim Cole, Jim Madden, and John Jackson. Figure 3. Fractography of 6 o’clock and 12 o’clock specimens at ~55 dpa and 18,000 appm He showing no appreciable difference.