Ph.D defense Djafar IABBADEN"Atomistic Simulations of Ultrafast Laser-induced Devitrification of Metallic Glasses"

"Atomistic Simulations of Ultrafast Laser-induced Devitrification of Metallic Glasses"

Abstract

Ultrafast laser processing is a modern method to tune nano-architectured material. A phase transformation can be triggered locally at nanometer scale. In this work, we tackled different problems to understand the complex mechanisms of the ultrafast laser-inducing transformations within the CuZr alloys. A qualitative approach is used in which Molecular Dynamics and Two Temperature Models are combined. Depending on the laser delivered fluence and pulse duration, the main phenomenon encountered is solid-solid phase transitions such as twining, defects generation, cavitation via solid-liquid phase change through the ablation process, and devitrification. Moreover, the analysis clearly shows that many factors can affect the final specimen as the initial phase structure, chemical stoichiometry.

Jury:

• Leonid ZHIGILEI, Referee, University of Virginia
• Anne TANGUY, Referee, INSA Lyon
• Jean-François PIERSON, Examiner, University of Nancy
• Jonathan AMODEO, Examiner, University of Aix Marseille
• Claudio FUSCO, Invited, INSA Lyon
• Dmitry IVANOV, Invited, University of Kassel
• Florence GARRELIE, Co-supervisor, University of Jean-Monnet
• Jean-Philippe COLOMBIER, Supervisor,  University of Jean-Monnet