Exploring Semi-solid Deformation of Al–Cu Alloys by a Quantitative Comparison Between Drained Die Compression Experiments and 3D Discrete Element Method Simulations
Journal
Minerals, Metals and Materials Series
ISBN
9783031225314
Date Issued
2023-01-01
Author(s)
Abstract
Developing computational modeling for semi-solid aluminum alloys with a solid network can help optimize advanced pressurized casting processes such as die-casting, squeeze casting, twin-roll casting, and semi-solid forging. However, a comprehensive numerical approach that can capture the coupled behavior between grain rearrangement and deformation of each individual grain remains a significant challenge. Inspired by recent synchrotron imaging work on deforming equiaxed-globular Al-Cu alloys showing granular deformation mechanisms, this research uses the particulate discrete element method (DEM) in 3D to generate two numerical assemblies of primary aluminum grains. Two-sphere particles and polyhedral grains were adapted in DEM to effectively represent aluminum crystals in 60% solid Al–15Cu alloy sample and 82% solid Al–8Cu alloy sample at 583 °C, respectively. Burgers contact model is introduced to consider viscous interactions between two grains at high temperatures. Contact model parameters are found by an iterative approach to reproduce the rheological response of compression experiments. Developments of 3D DEM simulations verified by compression experiments under controlled drained closed die boundary conditions will be useful for exploring the relationship among deformation process parameters and strain localization phenomena of a bulk semi-solid with enhanced microstructural sensitivity.
Subjects
Aluminum alloy | Discrete element method | Rheological modeling | Semi-solid | Solidification microstructures
Type
conference paper