Author:
Wang L.M.,Gong W.L.,Bordes N.,Ewing R.C.,Feit Y.
Abstract
AbstractThree compositions with the spinel structure (γ-AIVB2VIO4), MgAl2O4, FeCr2O4 and γ-SiFe2O4, have been irradiated with 1.5 MeV Kr+ ions over a temperature range (20 to 873 K). In situ TEM and HRTEM afterwork were conducted to characterize the effects of the ion irradiation on the microstructure. MgAl2O4 was the most “radiation-resistant” among the three materials. After irradiation to lx1016 ions/cm2 at 20 K, the cations were completely disordered among all possible tetrahedral and octahedral sites, but the oxygen sublattice remained intact. At room temperature, a high density of dislocation loops developed after this same dose, but there was no evidence of cation disordering. However, γ-SiFe2O4, a spinel structure type, formed under high pressure (7.0 GPa), was easily amorphized at low ion doses (σ1014 ions/cm 2) below 723 K, even lower than required for radiation-induced amorphization of its olivine polymorph, fayalite (α-SiFe2O4; HCP). At 873 K, the amorphous phase recrystallized to magnetite (Fe2+Fe 3+2O4, an inverse spinel structure) and quartz (SiO2) during continued Kr+ irradiation. Chromite (ideally FeCr2O4) with an actual composition of (Fe0.6Mg0.4)(Cr0.7A10.3)2O4 amorphized at 6x1015 ions/cm2 at 20 K, a dose about 20 times as high as that required to amorphize most other AB2O4 phases under the same irradiation conditions. A structural parameter, which quantifies the deviation from ideal packing in the spinel structure was developed and correlates with themeasured doses required for amorphization among these three spinel compositions.
Publisher
Springer Science and Business Media LLC
Cited by
12 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献