Indentation testing on 3 MeV proton irradiated tungsten

Scaling of deuterium retention in <3 MeV proton damaged Beryllium, Eurofer, and W-5Re in the range of 0.0003 to 6 DPA

“…While 3 MeV protons induce fewer displacements per ion (DPI) compared to heavy ion irradiation, this physical disadvantage is compensated by technical aspects resulting in largely higher beam currents and smaller beam spots achievable with protons. TEM observations with similar proton irradiated materials showed increasing defect density with DPA up to a saturation limit around 0.2 DPA in tungsten from where on mostly the loop defect size increased with constant loop density [5]. Also [6] found saturation effects in the 0.2 DPA region with a factor 5.5 increase in retention at 300 K, but by using heavy ions with 1 μm damage range.…”

Simultaneous irradiation and thermal effects on 16 MeV proton irradiated tungsten samples

“…However, as the range is restricted to 300 μm, internal target vacancies from SRIM are substituted for displacements per ion (DPI) in equation (2). For an atomic material density ρ, the proton current I projected on spot size S in range R as per equation (2) provides the damage dose rate DPA(t) [10]. This corresponds to a dose rate of 4.3 × 10 −7 dpa • s −1 culminating in a damage dose of 0.006 dpa.…”

“…While the damage cluster size produced by low energy proton irradiation is smaller as compared to heavy-ion damage, the damage clusters are spaced further apart, similar to neutron interactions [9]. Another approach, which is followed in this work, is based on the use of the linear pre-Bragg damage region, as previously described in [10]. Using higher energy protons (12-30MeV), as shown in figure 1 for 16 and 30 MeV protons on tungsten(W), the range of proton damage in the plateau region prior to the Bragg peak is over 300 μm and can be used to investigate macroscopic properties.…”