Peculiarities of Radiation Synthesis of MeWO4 Ceramics

Abstract

We report the results of MeWO₄ ceramics synthesis by the direct exposure of metal (Mg, Ca, Zn, W) oxides mixture to a high-power flux of high-energy electrons. The oxide powder particle sizes are 1–10 microns. The synthesis occurs with high efficiency in less than 1 s without the use of any additional substances and energy sources. The purpose of this work is to establish the main processes that ensure the effective synthesis of MgWO₄, CaWO₄, and ZnWO₄ ceramics from ZnO, CaO, MgO, and WO₄ oxides, which differ significantly in their physical and chemical properties. It has been found that the dependence of synthesis efficiency on the electron beam power density and the power density threshold at which synthesis begins varies significantly for simple metal oxides and is very close for the tungstates of these metals. The most probable explanation for the observed effect is redistribution of absorbed radiation energy. WO₃ powder particles have a high absorptance of the incident electron radiation. The result is a cascade multiplication of primary electrons into secondary electrons with much lower energy. Secondary electrons are efficiently absorbed by MgO, CaO, and ZnO particles, leading to their efficient decomposition and the formation of a new phase.

Keywords

Oxide ceramics / Tungsten / Radiation synthesis / Electron beam irradiation / Power density

Acknowledgments

The authors are grateful to E.F. Polisadova of Tomsk Polytechnic University for her assistance in organizing measurements of the granulometric composition of precursors.

Statement of the Use of Generative AI and AI-Assisted Technologies in the Writing Process

AI tools were used for language translation (with the authors taking full responsibility for the final content).

Author Contributions

Conceptualization, V.L.; Methodology, G.A. and Z.B.; Validation, V.L. and A.K.; Formal Analysis, D.M. and D.A.; Investigation, Z.B.; Resources, M.G.; Data Curation, A.K.; Writing—Original Draft Preparation, Z.B. and V.L.; Writing—Review & Editing, A.K.; Visualization, Z.B. and A.K.; Supervision, V.L.; Project Administration, V.L.; Funding Acquisition, V.L.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data will be available on request.

Funding

This research was funded by the Russian Science Foundation, grant number 23-73-00108. https://rscf.ru/project/23-73-00108/ (accessed on 23 January 2026).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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