کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1482687 991573 2011 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Molecular dynamics simulation of radiation damage in glasses
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Molecular dynamics simulation of radiation damage in glasses
چکیده انگلیسی

Molecular dynamics simulations of the ballistic effects arising from displacement cascades in glasses have been investigated in silica and in a SiO2–B2O3–Na2O glass. In both glasses the T-O-T′ angle (where T and T′ are network formers) diminishes, despite radiation causes opposite effects: while the ternary glass swells and silica becomes denser. We show that radiation-induced modifications of macroscopic glass properties result from structural change at medium/range, reflecting an increasing disorder and internal energy of the system. A local thermal quenching model is proposed to account for the effects of ballistic collisions. The core of a displacement cascade is heated by the passage of the projectile, then rapidly quenched, leading to a process that mimics a local thermal quenching. The observed changes in both the mechanical and structural properties of glasses eventually reach saturation at 2 1018 α/g as the accumulated energy increases. The passage of a single projectile is sufficient to reach the maximum degree of damage, confirming the hypothesis postulated in the swelling model proposed by J.A.C. Marples.

Research highlights
► Simulation of radiation effects in pure silica and a SiO2–B2O3–Na2O glass.
► Correlation between the macroscopic and structural modifications.
► Validation of the Marple's model to explain the swelling.
► Analogies and differences between the behaviors of SiO2 and SiO2–B2O3–Na2O.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Non-Crystalline Solids - Volume 357, Issue 14, 1 July 2011, Pages 2763–2768
نویسندگان
, , , ,