The surface damage of polycrystalline molybdenum and TZM alloy under 40‐, 60‐, and 120‐keV D+ impact has been investigated for irradition in both pulsed and continuous modes for total doses varying from 1.7×1017 to 2.2×1019 ions/cm2 and for target temperature varying from ambient temperature to 400° C. Analysis by scanning electron microscopy of the Mo samples held at ambient temperatures during D+ irradiations in both pulsed and continuous modes revealed surface damage due to blistering for the 40‐ and 60‐keV irradiations for doses ranging from 8.7×1017 to 8.1×1018 ions/cm2, but no detectable damage for the 120‐keV D+ irradiations for doses ranging from 4.3×1018 to 2.2×1019 ion/cm2. This observed difference in the blistering behavior is attributed to the difference in the ambient target temperature for the 120‐keV irradiation and both the 40‐ and 60‐keV irradiations. For irradiations at temperatures above 300° C, no blisters could be detected for any of the three energies. For similar irradiation conditions, TZM alloy showed a reduction in blistering as compared to molybdenum.