Dislocation relaxation processes due to kink migration

The interpretation of the Bordoni relaxation and of related relaxation phenomena in terms of the thermally activated, stress-assisted formation of kink pairs on dislocation lines is well established on assuming that the migration of kinks along dislocation lines is described by a high kink mobility...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Hermida, E.B., Seeger, A., Ulfert, W.
Formato:	JOUR
Materias:	Differential equations Dislocations (crystals) Enthalpy Internal friction Relaxation processes Shear stress Activation enthalpy Bordoni relaxation Kink migration Kink mobility Kink pair formation Thermal kink Metals
Acceso en línea:	http://hdl.handle.net/20.500.12110/paper_11554339_v6_n8_pC8_Hermida
Aporte de:	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires

id	todo:paper_11554339_v6_n8_pC8_Hermida
record_format	dspace
spelling	todo:paper_11554339_v6_n8_pC8_Hermida2023-10-03T16:08:08Z Dislocation relaxation processes due to kink migration Hermida, E.B. Seeger, A. Ulfert, W. Differential equations Dislocations (crystals) Enthalpy Internal friction Relaxation processes Shear stress Activation enthalpy Bordoni relaxation Kink migration Kink mobility Kink pair formation Thermal kink Metals The interpretation of the Bordoni relaxation and of related relaxation phenomena in terms of the thermally activated, stress-assisted formation of kink pairs on dislocation lines is well established on assuming that the migration of kinks along dislocation lines is described by a high kink mobility μ k . This assumption, however, is not valid if the activation enthalpy for kink migration, H m , is comparable with or even larger than the formation enthalpy of kink pairs or if even when small compared with the formation energy of kinks, H m is larger than the lowest thermal energies accessible in internal friction experiments. In those cases not only migration but also annihilation and trapping of thermal kink pairs may produce internal friction peaks. The difference-differential equations governing the thermal kink pairs evolution along dislocation lines under the action of a homogeneous applied shear stress are set up and their time-dependent solutions characterized by a set of relaxation times. It is shown how to obtain, from these solutions, the internal friction spectrum under conditions that are experimentally realized. Quantitative descriptions of geometrical kink migration and kink pair evolution are compared with selected experimental results. Fil:Hermida, E.B. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_11554339_v6_n8_pC8_Hermida
institution	Universidad de Buenos Aires
institution_str	I-28
repository_str	R-134
collection	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic	Differential equations Dislocations (crystals) Enthalpy Internal friction Relaxation processes Shear stress Activation enthalpy Bordoni relaxation Kink migration Kink mobility Kink pair formation Thermal kink Metals
spellingShingle	Differential equations Dislocations (crystals) Enthalpy Internal friction Relaxation processes Shear stress Activation enthalpy Bordoni relaxation Kink migration Kink mobility Kink pair formation Thermal kink Metals Hermida, E.B. Seeger, A. Ulfert, W. Dislocation relaxation processes due to kink migration
topic_facet	Differential equations Dislocations (crystals) Enthalpy Internal friction Relaxation processes Shear stress Activation enthalpy Bordoni relaxation Kink migration Kink mobility Kink pair formation Thermal kink Metals
description	The interpretation of the Bordoni relaxation and of related relaxation phenomena in terms of the thermally activated, stress-assisted formation of kink pairs on dislocation lines is well established on assuming that the migration of kinks along dislocation lines is described by a high kink mobility μ k . This assumption, however, is not valid if the activation enthalpy for kink migration, H m , is comparable with or even larger than the formation enthalpy of kink pairs or if even when small compared with the formation energy of kinks, H m is larger than the lowest thermal energies accessible in internal friction experiments. In those cases not only migration but also annihilation and trapping of thermal kink pairs may produce internal friction peaks. The difference-differential equations governing the thermal kink pairs evolution along dislocation lines under the action of a homogeneous applied shear stress are set up and their time-dependent solutions characterized by a set of relaxation times. It is shown how to obtain, from these solutions, the internal friction spectrum under conditions that are experimentally realized. Quantitative descriptions of geometrical kink migration and kink pair evolution are compared with selected experimental results.
format	JOUR
author	Hermida, E.B. Seeger, A. Ulfert, W.
author_facet	Hermida, E.B. Seeger, A. Ulfert, W.
author_sort	Hermida, E.B.
title	Dislocation relaxation processes due to kink migration
title_short	Dislocation relaxation processes due to kink migration
title_full	Dislocation relaxation processes due to kink migration
title_fullStr	Dislocation relaxation processes due to kink migration
title_full_unstemmed	Dislocation relaxation processes due to kink migration
title_sort	dislocation relaxation processes due to kink migration
url	http://hdl.handle.net/20.500.12110/paper_11554339_v6_n8_pC8_Hermida
work_keys_str_mv	AT hermidaeb dislocationrelaxationprocessesduetokinkmigration AT seegera dislocationrelaxationprocessesduetokinkmigration AT ulfertw dislocationrelaxationprocessesduetokinkmigration
_version_	1782026175157108736

Dislocation relaxation processes due to kink migration

Ejemplares similares