"PhD - Phase-Field Modelling of Martensitic Transformation in TRIP Refractory High-Entropy Alloys"

Offer Description

Context

Refractory high-entropy alloys (RHEAs) and complex concentrated alloys (RCCAs) are subclasses of multi-principal element materials with high strength and thermal stability at both ambient and high temperatures. These alloys, typically formed from transition metals of Groups IV (Ti,Zr,Hf) and V-VI (V,Nb,Ta,Cr,Mo,W) crystallize in a body-centered cubic (β) solid-solution phase. Despite their excellent high-temperature performance, their limited room-temperature ductility and low work-hardening rates has hindered practical applications.

Recent advances have revealed that transformation-induced plasticity (TRIP) can significantly improve ductility and work-hardening in certain RHEAs, particularly those containing Group IV elements (Ti, Zr, Hf). Understanding and controlling this TRIP effect is crucial to overcome the strength-ductility trade-off enabling next-generation high-temperature structural materials.

Scientific objectives

This internship is part of a broader ANR (French National Research Agency) project “BADTRIP” aimed at understanding the micro-mechanical and microstructural mechanisms governing martensitic transformation in TRIP-type RHEAs at room temperature.

The specific goal of this internship is to develop and validate a 3D phase-field model capable of describing:

• The early stages of martensitic transformation in RHEAs.
• The growth and interaction of martensitic variants within a metastable β matrix.
• The coupling between transformation-induced strains and plastic relaxation of the matrix.

Ultimately, the results will help establish physically based criteria for predicting TRIP behaviour in RHEAs.

Main tasks

• Familiarize yourself with an existing multi-phase-field model for martensitic transformations.
• Extend the existing model to include plastic relaxation of the β matrix.
• Calibrate input parameters (lattice constants, elastic constants, free energies, yield stresses, etc.) from literature data.
• Perform numerical simulations to investigate the effect of mechanical loading on the microstructural evolution.
• Analyse 3D simulation outputs and compare with available experimental data.

Where to apply

E-mail maeva.cottura@univ-lorraine.fr

Requirements

Research Field Physics » Computational physics

Education Level Master Degree or equivalent

Research Field Physics » Classical mechanics

Education Level Master Degree or equivalent

Research Field Physics » Thermodynamics

Education Level Master Degree or equivalent

Skills/Qualifications

• Strong background in metallurgy, materials science, solid mechanics, or computational physics.
• High interest in numerical methods and scientific programming (e.g. Python, Fortran).
• Knowledge of phase field modelling is appreciated.
• Good written and spoken English and/or French.

Languages ENGLISH

Level Good

Work Location(s)

Number of offers available 1

Company/Institute Institut Jean Lamour

Country France

City Nancy

Postal Code 54011

Contact

City Nancy

Website https://ijl.univ-lorraine.fr/

Street 2 Allée André Guinier

Postal Code 54000