DEUTERIUM AND HELIUM ION IRRADIATION EFFECTS ON TIB2 COATINGS

The surface damage and erosion of chemically vapor deposited TiB2 coatings and commercial grade titanium, caused by 40, 60 and 120 keV D+ and 4He+ irradiation, have been studied for the as-deposited coatings and for coating surfaces that were mechanically polished prior to irradiation. Scanning electron microscopy analysis of polished TiB2 samples irradiated with D+ and 4He+ to a dose of 3.1 × 1018 ions cm-2 reveals significant surface damage due to blistering and flaking, whereas for identical irradiation conditions the as-deposited TiB2 coatings show very little damage. For similar irradiation conditions the titanium metal samples showed blistering for the 4He+ irradiation case but no significant surface damage for the D+ case. Estimates of the erosion yields due to blister exfoliation in polished TiB2 samples show an increase with increasing projectile energy for the total dose studied. © 1979.