In situ TEM of radiation effects in complex ceramics

Abstract

In situ transmission electron microscopy (TEM) has been extensively applied to study radiation effects in a wide variety of materials, such as metals, ceramics and semiconductors and is an indispensable tool in obtaining a fundamental understanding of energetic beam-matter interactions, damage events, and materials' behavior under intense radiation environments. In this article, in situ TEM observations of radiation effects in complex ceramics (e.g., oxides, silicates, and phosphates) subjected to energetic ion and electron irradiations have been summarized with a focus on irradiation-induced microstructural evolution, changes in microchemistry, and the formation of nanostructures. New results for in situ TEM observation of radiation effects in pyrochlore, A(2)B(2)O(7), and zircon, ZrSiO(4), subjected to multiple beam irradiations are presented, and the effects of simultaneous irradiations of alpha-decay and beta-decay on the microstructural evolution of potential nuclear waste forms are discussed. Furthermore, in situ TEM results of radiation effects in a sodium borosilicate glass subjected to electron-beam exposure are introduced to highlight the important applications of advanced analytical TEM techniques, including Z-contrast imaging, energy filtered TEM (EFTEM), and electron energy loss spectroscopy (EELS), in studying radiation effects in materials microstructural evolution and microchemical changes. By combining ex situ TEM and advanced analytical TEM techniques with in situ TEM observations under energetic beam irradiations, one can obtain invaluable information on the phase stability and response behaviors of materials under a wide range of irradiation conditions.

<i>In-Situ</i> Observation of Radiation Damage Using a Combined Facility of Electron Microscope and Heavy-Ion Accelerator(s) &mdash;History and Future Prospectives&mdash;

“…For those who might be interested in this field, I will refer two papers related to in situ TEM observation of non-metallic solids, for intermetallics 39) and complex ceramics. 40) Apart from heavy ion radiation damage, there are numerous interesting phenomena other than cascade damage. There are many unexplored area in that respect, which might become very interesting and important in the future.…”

Fast crystallization of amorphous Gd2Zr2O7 induced by thermally activated electron-beam irradiation

“…In some positions, the rapid grain growth rate may be attributed to the ionization-enhanced effects of the e-beam. 15 Research on the ionization effect versus displacement cascade events has attracted increasing interest. Based on integrated experimental techniques and computational approaches, researchers have studied the separated and coupled response of some ceramic materials to ion energy loss by electronic energy loss (ionization effects) and nuclear energy loss (displacement events).…”

“…15,16,24,25 Therefore, a complementary experiment was conducted for the further study of the ionization effects. An amorphous Gd 2 Zr 2 O 7 pellet was irra- (200 keV e-beam) for apatite.…”

“…15,16 Contrary to disordering and amorphization induced by displacive incident ions through nuclear energy loss, e-beam irradiation has been reported to enhance the defect recovery, nucleation, and recrystallization through ionization and electronic excitation processes in many amorphous materials, such as strontium titanate, apatites, CaZrTi 2 [17][18][19][20][21][22][23][24][25] However, the crystallization induced by an e-beam may be attributed to a wide range of mechanisms, and the process is material dependent. The role of electronic deposition and the coupled dynamics of electronic and atomic processes need to be studied over a range of irradiation conditions to elucidate the underlying mechanisms for different classes of materials.…”

Damage Accumulation in Nuclear Ceramics

“…They may also be employed as cladding materials for gas-cooled fission reactors and structural components in fusion reactors. For all these applications, there is an urgent need of data concerning the behavior of nuclear ceramics upon irradiation.The topic that is concerned here is so broad that it requires a whole book to cover the main issues; the state of knowledge was regularly upgraded in thorough reviews [1][2][3][4][5][6][7][8][9][10]. To deal it in a short article, we focus on the presentation of a few remarkable examples concerning the ion-beam modifications of nuclear ceramics (zirconia, pyrochlores, silicon carbide, etc.)…”