High-temperature annealing behavior of ion-implanted spinel single crystals

Abstract

This paper reports modifications of the chemical and structural properties of MgAl2O4 single crystals implanted with Cs ions and submitted to high-temperature annealing. The composition changes, the damage created in the three sublattices (Al, Mg and O) of the crystals, and the behavior of implanted ions were studied by Rutherford backscattering and channeling experiments as a function of the Cs fluence and annealing temperature. The data show that annealing above 700–800 °C induces a huge modification of the stoichiometry of the material, a decrease of the lattice disorder, and an increase of the fraction of Cs atoms located in substitutional lattice sites. These results have to be taken into account for the future use of spinel as a matrix for the transmutation of nuclear waste.

Radiation effects in cubic zirconia: A model system for ceramic oxides

“…The same behavior is observed in CZ irradiated with a large variety of low energy ions [13], leading to the conclusion that the number of dpa is the key parameter for the evolution of the damage buildup in the nuclear collision regime. Similar results are also obtained in other non-amorphizable ceramics (for instance spinel and uranium dioxide) irradiated at low energy [21][22][23][24][25][26][27][28].…”

Damage Accumulation in Nuclear Ceramics

“…A similar behavior (except step 3) was observed in cubic zirconia irradiated with a large variety of low-energy ions [22,23], leading to the conclusion that the number of dpa is the key parameter for the evolution of the damage build-up in the nuclear collision regime. Multi-step damage accumulation processes were also reported in other non-amorphizable ceramics (for instance spinel, magnesium oxide and uranium dioxide) irradiated at low energy [24][25][26][27].…”

“…A S e threshold for track formation, depending on the material and on the ion velocity (about 20-30 keV/nm in cubic zirconia), was found in experiments using swift heavy ions of different masses. A single-step damage accumulation process is also reported for other non-amorphizable ceramics (for instance spinel, magnesium oxide and uranium dioxide) irradiated with swift heavy ions [24][25][26][27]. Figure 5 shows the variation of the accumulated damage (determined by RBS/C) as a function of the irradiation fluence for titanate pyrochore and silicon carbide (materials which are amorphizable by elastic collisions) irradiated with GeV heavy ions [28,29].…”

Use of channeling for the study of radiation effects in nuclear materials

“…Multi-step damage accumulation processes were also reported for other non-amorphizable (for instance spinel, magnesium oxide and uranium dioxide) and amorphizable (for instance titanate pyrochlores) nuclear materials irradiated with low-energy ions [27][28][29][30][31][32][33]. In all cases, the dose in dpa (/ 2 ) at which starts the second step of damage accumulation is a parameter which reflects the stability of materials upon ion irradiation: the highest / 2 , the greatest resistance to disordering or amorphization.…”