Avalanche Dynamics and Magnetoelastic Coupling in Metallic Glasses

by Carlos Herrero Gómez
Doctoral thesis
Date of Examination:2018-01-24
Date of issue:2018-02-19
Advisor:Prof. Dr. Konrad Samwer
Referee:Prof. Dr. Konrad Samwer
Referee:Prof. Cynthia Volkert
Persistent Address: http://dx.doi.org/10.53846/goediss-6735

 

 

Files in this item

Name:Thesis_Herrero.pdf
Size:7.05Mb
Format:PDF

The following license files are associated with this item:

Abstract

English

This work is devoted to the study of the magnetoelastic coupling in metallic glasses. Such study is done by means of the statistical analysis of the intermittency of the deformation signal yield as a consequence of a superposition of mechanical and magnetic excitation. That intermittency is analysed and interpreted in the framework of avalanche dynamics. This memoir is divided in three sections, which focus on the analysis of avalanches yield by a non-magnetic glass, by a magnetic glass exposed to creep deformation, and by different magnetic glasses exposed to stress-strain tests. The experimental results show that there is a crossover in the distribution of avalanches produced during creep deformation. Such crossover takes place both for the magnetic and non-magnetic alloys and can be interpreted in terms of a transition in the deformation mechanism. Additionally, the data suggest that mechanical avalanches are maximized for a certain magnetization orientation in the case of magnetostrictive metallic glasses.
Keywords: metallic glasses; avalanche dynamics; magnetoelastic coupling
 
Statistik