Chelsey Hargather, PhD

Adjunct Faculty

Materials and Metallurgical Engineering

chelsey.hargather@os-tw.com
575 - 835 - 5582
Jones 15

Website

Video: 10 min Research Talk

Research Areas

Improvement of Ni-base superalloys used in commercial jet engine applications using first-principles calculations and CALculation of PHAse Diagrams (CALPHAD) modeling technique.
First-principles calculations of self-, dilute, and non-dilute diffusion coefficients in fcc and bcc metals.
Database development of Ni-base superalloy systems using the CALPHAD approach.

Education

Ph.D. Materials Science and Engineering, The Pennsylvania State University, 2012

B.S. in Materials Science and Engineering, Virginia Polytechnic Institute and State University, French Minor, 2008

Plain Language Summaries of Recent Research

First-principles calculations of diffusion coefficients in metals and metal alloy systems

The diffusion coefficients of an alloy system are critical to understanding phase formation, mechanical properties, and failure mechanisms such as a creep. Our group calculates vacancy mediated self- dilute impurity- and non-dilute impurity diffusion coefficients and associated thermodynamic properties as a function of temperature for a variety of metal alloy systems. We are currently exploring the importance of vibrational entropy on the diffusion coefficient calculations, as well as calculating non-dilute impurity diffusion coefficients in the Ag-Au system.

Recent Publications

C. Z. Hargather, S. L. Shang, and Z. K. Liu, A comprehensive first-principles study of solute elements in dilute Ni alloys: Diffusion coefficients and their implications to tailor creep rate, under review, Acta Materialia, 2018.

CZ Hargather, SL Shang, Y Du, and ZK Liu, A first-principles study of self-diffusion coefficients of fcc Ni, Computational Materials Science, 86C, (2014), 17-23.

Recent Presentations

C. Z. Hargather, H. Lee, J. M. O'Connell, S. L. Shang, Z. K. Liu, First-principles calculations of factors contributing to non-dilute impurity diffusion coefficients in Metals, Materials Science and Technology (MS&T 2017) Annual meeting, October 2017.

J. M. O'Connell, K. Mackowski, C. Z. Hargather, Effects of DFT exchange correlation functional on the accuracy of diffusion migration energies in Ag, Cu, and Ni systems, Materials Science and Technology (MS&T 2017) Annual meeting, October 2017.

H. Lee, J. M. O'Connell, C. Z. Hargather, The effects of entropy on diffusivity determined by first-principles calculations, Student Research Symposium, New Mexico Tech, April 2017.

Efficient computational methodology for calculating elastic properties of High Entropy Alloys

High entropy alloys are a new class of engineering materials composed of equal or nearly equal quantities of five or more metals in a single solid solutions phase. With more research, they have the potential to replace conventional alloy systems in a variety of applications because of their improved strength-to-weight ratios, and high corrosion and oxidation resistance. Our group is currently focusing on developing more efficient computational methodologies using density functional theory to investigate slip and deformation behavior of various fcc and bcc high entropy alloy systems.

Recent Publications

AM Scheer, JD Strother, CZ Hargather, First-principles calculations of stacking fault energies in quinary high-entropy alloy systems, Proceedings of the 2018 TMS Annual Meeting (The Minerals, Metals, and Materials Society), accepted, 2018.

Recent Presentations

M. Scheer, J. D. Strother, C. Z. Hargather, First-principles calculations of stacking fault energies in quinary high-entropy alloy systems, Materials Science and Technology (MS&T 2017) Annual meeting, October 2017.

M. Scheer, J. D. Strother, C. Z. Hargather, Computational Investigation of High Entropy Alloys (HEAs), Student Research Symposium, New Mexico Tech, April 2017.

M. Scheer, J. D. Strother, C. Z. Hargather, Computational Investigation of High Entropy Alloys (HEAs), American Scoeity for Metals (ASM International) Regional Albuquerque Chapter meeting, March 2017.

Thesis

An efficient computational methodology for calculating properties of fcc high entropy alloys – A. Scheer, (2018)