Computational Materials System Design Prof. Zi-Kui Liu. Phases Research Lab Materials Science | Physics | Chemistry | Thermodynamics . Why computational? broad applications | intellectually challenging | more publications | green | economical . Modeling
Prof. Zi-Kui Liu
Phases Research Lab Materials Science | Physics | Chemistry | Thermodynamics
Why computational? broad applications | intellectually challenging | more publications | green | economical
across length scales
Modeling of Ti-6Al-4V for Additive Manufacturing
Bio-compatible Titanium Alloys
First-principles calculations are used to predict thermochemical properties of phases where experimental data is not available
Density Functional Theory
HΨ = EΨ
Current biomedical prosthetic devices used especially in knee and hip replacements have a higher elastic modulus than that of bone.
Additive manufacturing (AM) has enabled unprecedented control over the design of bulk alloys. A significant challenge associated with producing parts by laser-based AM methods is that a part's thermal history is a complex function of material properties, process parameters and part geometry. In this project thermodynamic and
kinetic models are developed and
used to predict the metastable phase
compositions that occur during the
additive manufacture of Ti-6Al-4V.
These models will also be
extended to compositionally-graded
VASP: PAW PBE-GGA
Phonon dispersions, band structures, etc.
This can often lead to “stress shielding,” a key mechanism of implant failure. The project focuses on alloying titanium, which already has a relatively low elastic modulus, with other bio-compatible elements Mo, Nb, Sn, Ta, Zr to be able to match the elastic modulus of bone. By modeling the thermodynamic behaviors and elastic constants we hope to accelerate the design of this family of alloys.
E0 V0 B B’
Finite temperature predictions
S(T) and Cp(T)
CALPHAD Phase Description
Fedotov, Phys. Met. Metall., 1985; Zhou, Mat Sci Eng A, 2004; Zhou, Mater Sci+, 2009; Zhou, Matser T, 2007;
*V. L. Moruzzi, J. F. Janak, and K. Schwarz, Phys. Rev. B 37, 790 (1988).
What we do
High Energy Density Cathodes for Li-ion Batteries
Input: Crystal Structure
NSF: “SEP Collaborative: Routes to Earth Abundant Kesterite-based Thin Film Photovoltaic Materials”
NSF: “Computational and Experimental Investigations of Magnesium Alloys”
NETL: “Computer-Aided Development of Novel New Materials for High Temperature Applications”
US Army Research Laboratory: “Computational Thermodynamic Modeling and Phase Field Simulations for Property Prediction in Advanced Material Systems”
AirProducts, Inc.: “Thermodynamic modeling of perovskites”
US Air Force: “Corrosion protection for magnesium alloys – development of novel, environmentally compliant, magnesium coatings system with tailored properties”
US Air Force: “Cast Eglin Steel Development”
Li-ion rechargeable batteries are key constituent for high-energy-density storages needed for applications such as electronic devices. In this project we investigate a new class of Li- and Mn-rich layered cathode material residing in a multi-component space of xLi2MnO3∙(1-x)LiMO2 with M being Cr, Mn, Fe, Co and Ni.
By using first-principles calculations the effects of these alloying elements are studied and potential outliers are searched for. In combination to calculations, cathode materials are synthesized and characterized within the collaboration with the Dept. of Mechanical and Nuclear Engineering.
Zhong, CALPHAD, 2005
Arroyave, PRB, 2006