8th World Congress on Integrated Computational Materials Engineering (ICME 2025): PSP Linkages: Multiscale/Multiphysics Modeling II
Program Organizers: Victoria Miller, University of Florida; Stephen DeWitt, Oak Ridge National Laboratory
Monday 2:30 PM
June 16, 2025
Room: Platinum Ballroom 3
Location: Anaheim Marriott
Session Chair: Avik Mahata, Merrimack College
2:30 PM Invited
Microstructures and Properties of AlCrFeMnV, AlCrFeTiV, and AlCrMnTiV High-Entropy Alloys: Keith Knipling1; Patrick Callahan1; 1Naval Research Laboratory
A series of high-entropy alloys (HEAs) containing AlCrFeMnV, AlCrFeTiV, and AlCrMnTiV have been designed using a combination of thermodynamic prediction by Thermo-Calc and by experimental observation of the microstructure and phases present in arc-melted alloys. These alloys are predominantly BCC, with some alloys forming additional minor phases. A particularly intriguing microstructure is observed in the AlCrMnTiV alloy, which contains a high number density of ∼50 nm ordered BCC cuboids that are coherent with the BCC matrix, resembling the well-known γ-γ' microstructures in Ni-based superalloys but in a BCC system. We will correlate the alloy microsctructures, observed using a combination of X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM/TEM), and atom-probe tomography (APT), to the alloys’ mechanical properties measured by Vickers microhardness and nanoindentation.
3:00 PM Break
3:30 PM
Mean-Field Modeling of Precipitation in Mg-Zn-Ca(-Ag) Alloys: Insights Into Ageing and Strengthening Mechanisms: Yanheng Xie1; Magnus Anderson2; Claire Utton1; Miguel Espadero1; Dikai Guan3; Matthew Murphy4; Hector Basoalto1; 1The University of Sheffield; 2Thermo-Calc software AB; 3Southampton University; 4Luxfer MEL Technologies
Mg-Zn-Ca(-Ag) alloys exhibit excellent mechanical properties and biodegradability, making them promising candidates for biomedical applications. The addition of Ag can further enhance precipitation strengthening by refining the distribution and kinetics of Mg-Zn secondary phases. This study investigates the effects of solidification and heat treatment on Mg-3Zn-0.2Ca and its Ag-containing variants. Scheil solidification model is used to simulate the formation of intermetallic compounds, while the mean-field precipitation model predicts the evolution of secondary precipitate particles during ageing. Additionally, a dislocation bowing model is employed to describe the influence of precipitate evolution on mechanical properties. Experimental validation through EDX, EBSD, and mechanical testing characterises microstructure and mechanical performance. Results indicate that Ag addition accelerates precipitate formation and ageing response. These findings provide insights into optimising alloy composition and heat treatment to balance strength and microstructural stability, contributing to the development of Mg-Zn-Ca(-Ag) alloys for lightweight and biomedical applications.
3:50 PM
Computation of Phase Fractions from Continuous Heating Dilatation Experiment for a Medium Mn Steel: Kamal Kumar Gupta1; Shiv Brat Singh1; 1Indian Institute of Technology Kharagpur
The computation of calculation of austenite fraction and its carbon content has been performed using Newton's method that minimizes error between calculated percentage change in length and experimentally recorded percentage change in length at each temperature step up to temperature above Ac3 from dilatation data obtained on heating Fe-0.2C-5Mn-0.8Si-0.4Al medium Mn steel having initial retained austenite in martensitic micro structure for different heating rate 1,25 and 50 degree Celsius per second. The simulated change in pct. length is approximated as one third of the pct. change in volume, where volume at any temperature is proportional to sum of multiplication of mole fraction of phase and unit volume in that phase considering both mole fraction of phases and its unit volume can change with temperature.
4:10 PM
Multi-Scale Investigation of Dislocation-Precipitate-Grain Boundary Interactions in Precipitation-Hardened Al-Cu Alloys: Anantha Lakshmi Prasanna Tatavarty1; Amit Singh1; Sushil Mishra1; 1Indian Institute of Technology Bombay
This study employs a multi-scale approach to investigate the mechanical behaviour of precipitation-hardened Al-Cu alloys, focusing on dislocation-precipitate-grain boundary interactions. Molecular statics simulations validate equilibrium configurations from prior analytical models, capturing atomic-scale effects. Molecular dynamics (MD) simulations extract critical parameters, such as dislocation mobility and drag coefficients, which inform discrete dislocation dynamics (DD) studies. DD simulations analyze mesoscale dislocation behaviour and its dependence on microstructural features. These insights are integrated into crystal plasticity finite element modelling (CPFEM) to predict macroscopic deformation responses under varying conditions. This framework bridges atomistic, mesoscale, and continuum scales, providing a comprehensive understanding of the deformation mechanisms in precipitation-hardened Al-Cu alloys.