The permeation of 2–22‐keV deuterons implanted into 25‐&mgr;m‐thick cold‐rolled Ni foils was studied near room temperature. The results are generally characterized by a time lag &tgr; and a steady‐state permeation rateJ. The variation of &tgr; with beam intensity and temperature indicates an average relative concentration of ∼4×10−4of saturable bulk traps of binding energy 0.26±0.01 eV, plus a larger concentration of weaker traps. At the highest energy,Jis well described by theory.