Irradiation of titanium, zirconium, and hafnium nitrides with high-energy ions

Abstract

We have identified structural and morphological changes produced by irradiation with 167-MeV ⁺²⁴Xe¹³⁶ ions to a fluence of 5.3 × 10¹⁴ cm^–2 in Ti, Zr, and Hf nitrides prepared using oxidation-assisted engineering. Irradiation of TiN_x and HfN_x leads to the formation of nano- and micropores in the surface layer of the samples. The surface layer of ZrN_x samples contains nanopores both before and after irradiation. The presence of pores in the unirradiated ZrN_x samples probably ensures the possibility of structural relaxation without further pore formation under irradiation. The irradiated ZrN_x samples have local crystal structure distortions unrelated to dislocations and attributable to the impact of high-energy xenon ions.