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 1242015 | ANNUAL REPORT 113 Accomplishments In late 2011,AECL shipped several small, 1 mm x 1 mm cubes of irradiated X‑750 that had been removed from regions of interest in several garter springs. Figure 1 is a representation of a typical garter spring with the calculated temperature profile during service. Since temperature can contribute to embrittlement and it was noted that some regions of the springs exhibited ductility while others were severely embrittled, specimens were selected from spacer regions near the 6 o’clock position (lower tempera- ture due to pinching against the cooler calandria tube) and the 12 o’clock posi- tion (higher temperature). In addition to temperature variation, specimens were extracted from springs that had accu- mulated DPA levels between 6 and 55 and that contained differing levels of He between 1500 and 18,000 appm. During 2012 and into 2013, trans- mission electron microscopy (TEM) foils were produced using the active focused ion beam (FIB) at the INL’s Electron Microscopy Laboratory (EML). TEM analyses were then performed by a visitingAECL scientist at the CAES Microscopy and Characterization Suite (MaCS). In addition toTEM analysis, hardness of the specimen sections was obtained using a shielded microhardness tester at the INL EML. The collaboration between CNL and INL has advanced our understanding of reactor core components through the use of state-of-the-art microscopy facilities. — Colin D.Judge, R&D Scientist Figure 2. Fractography of 6 o’clock and 12 o’clock specimens at ~6 dpa and 1000 appm He.