Science & Technology Thrust (STT) 1
Multiscale Metal Forming and Pattern Replication
Research Objectives of STT1
- Understand plasticity and microstructural length scale effects.
- Understand and engineer solid/solid interfacial mechanical integrity.
- Combining experimentation with multiscale modeling/simulation.
- Demonstrate high-throughput fabrication technologies & structure/devices relevant to engineering applications.
An incomplete understanding of:
- Mechanical size effects as the characteristic dimension of plastic deformation approches the regime where materials’ mechanical mechanical responses exhibit a strong length scale dependence.
- Additional size effects as the characteristic dimension of deformation approaches the microstructural length scale of the material.
- Engineered interfaces between coatings and substrates in coated forming tools.
Research Examples: Progress and Accomplishments
Understanding Micron Scale Plasticity Size Effects
Flow Stress of Confined Thin Plastic Layers as a Function of Geometry and Microstructure
MRS Communications, 6, 289-294 (2016).
Engineering the Mechanical Integrity of Solid/Solid Interfaces
Quantitative Testing of Mechanical Integrity of Coating/Substrate Interfaces
J. Materials Research, doi:10.1557/jmr.2016.516 (2017).
Demonstrating High-Throughput Micromanufacturing Technologies
Instrumented Microscale Roll Molding Allows Metal-Based Microscale Structures to be Fabricated in a Continuous Roll-to-Roll Printing Fashion
Roll Molded One- and Two-Dimensional (1D/2D) Aluminum Micro Fin Array Structures
J. Micromechanics & Microengineering 27, 025012/1-9 (2017).
Metal/Ceramics Interfacial Shear Failure at Critical Strain
The shear response of the metal/ceramic interface is modeled using a Ti-TiN bi-crystal using MEAM potential.
The structure of the interface is studied, and the shear response is also considered by subjecting the bicrystal in to a pure shear loading.
Modeled in MD using Ti-TiN bilayer system, using MEAM potential.
Structure of the Misfit Dislocation Network (MDN) Depends on the Orientation of Ti
Interfacial Shear Failure is Associated with Motion of MDN with Low Shear Strength
DFT Calculations on Coherent Interfaces Provide Confidence to MD Predictions