Analysis of trapping sites for deuterium in W-Cr-Y SMART alloy

Deuterium (D) retention in tungsten-chromium-yttrium (W-Cr-Y) alloy depending on the irradiation fluence of 1019(-5) x 10(21) D/m(2) at various sample temperatures in the range of 300-900 K was investigated using in-situ thermal desorption spectroscopy (TDS). The irradiation was carried out using 2 keV D-3(+) ions (670eV/D). An increased D retention compared to that of pure polycrystalline W and additional high-temperature peaks were observed in TDS. The de-trapping energy of 2.21 +/- 0.05 eV for these traps was determined by the Kissinger method using the series of experiment with different heating rates. The total D retention dropped down at elevated irradiation temperatures and was rather small at 900 K, but has a local maximum at about 700 K.