| Texto completo | |
| Autor(es): |
Lancelotti, Ricardo Felipe
;
Rodrigues, Ana Candida Martins
;
Zanotto, Edgar Dutra
Número total de Autores: 3
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of the American Ceramic Society; v. 106, n. 10, p. 8-pg., 2023-06-27. |
| Resumo | |
Relaxation occurs spontaneously in all glasses and is a fundamental step of important technological processes, such as annealing, crystal nucleation, and chemical strengthening by ion exchange. Despite extensive studies over the past decades, there are still conflicting results on whether the kinetics of structural relaxation depends on the analyzed property. Thus, in this study, we used a lithium disilicate glass as a model composition to determine the structural relaxation kinetics during physical aging experiments by measuring the time evolution of the refractive index and ionic conductivity down to 35 K below the initial fictive temperature. In all cases, variations in these properties were adequate to capture the structural changes throughout the aging experiments. At each temperature, the experimental relaxation data fit quite well with the classical stretched exponential relation. We also found that the relaxation process starts faster when probed by ionic conductivity than by refractive index; however, they show similar average relaxation times. These very small structural rearrangements are always the same, but ionic conductivity changes faster than refractive index at the beginning of the process. Our comprehensive results strongly indicate that relaxation dynamics is indeed dependent on the analyzed property. (AU) | |
| Processo FAPESP: | 21/03374-5 - Relaxação estrutural de vidros e sua influência em outros processos dinâmicos |
| Beneficiário: | Ricardo Felipe Lancelotti |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 13/07793-6 - CEPIV - Centro de Ensino, Pesquisa e Inovação em Vidros |
| Beneficiário: | Edgar Dutra Zanotto |
| Modalidade de apoio: | Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs |