Lawrence Livermore National Laboratory



Computation-Focused High Temperature Alloy Design - Postdoctoral Researcher

Location:  Livermore, CA
Category:  Post Docs
Organization:  Physical and Life Sciences
Posting Requirement:  External w/ US Citizenship
Job ID: 107557
Job Code: Post-Dr Research Staff 1 (PDS.1)
Date Posted: September 22 2020

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Join us and make YOUR mark on the World!

Come join Lawrence Livermore National Laboratory (LLNL) where we apply science and technology to make the world a safer place; now one of 2020 Best Places to Work by Glassdoor!

We have an opening for a computation-focused Postdoctoral Researcher to work in the area of high-temperature alloy design and actively participate in research dedicated to uncovering the microstructural origins of the exceptional mechanical properties of high entropy alloys (HEAs) and discovering new refractory HEAs (RHEAs) for targeted high-temperature applications. You will be a creative force in the development and application of physics-based computational models for dislocation-mediated plasticity (e.g. phase-field / phase-field crystal) and physics- and data-based methods for mechanical property prediction (e.g. mechanistic yield stress models and machine learning models), and integrate these models / results into an alloy design framework that uses optimization methods to rapidly screen for promising compositions over the vast multicomponent HEA phase space. This position is in the Actinides and Lanthanides group within the Materials Science Division.

Essential Duties
- Propose, develop, and integrate solid-solution strengthening models (e.g. mechanistic / analytical and machine learning-based) for HEAs into LLNL’s alloy design framework (Materials Design Simulator).
- Develop, verify, validate, and maintain a phase-field crystal simulation code for HEAs on LLNL supercomputers.
- Understand and elucidate high-temperature strengthening mechanisms in RHEAs.
- Generate and maintain a database of phase stability and mechanical properties for HEAs.
- Interface with experimentalists to validate models and propose directions and guidance for RHEA property optimization.
- Work both independently and collaborate with others in a multidisciplinary team environment to accomplish program goals.
- Publish research results in peer-reviewed scientific or technical journals and present results at external conferences, seminars, and/or technical meetings.
- Perform other duties as assigned.

Qualifications
- PhD in materials science, condensed matter physics, applied math, or a related field.
- Experience and knowledge in at least two of the following areas: alloy mechanical property prediction, phase-field modeling, dislocation modeling, numerical optimization, HEA science.
- Ability to independently develop massively parallelized codes using Fortran, C/C++, Python, and advanced numerical solvers.
- Experience with numerical methods for solving partial differential equations such as finite difference, finite element, and/or spectral methods.
- Knowledge of alloy metallurgy, including thermodynamics / phase stability, phase transformations, defect structure and kinetics.
- Proficient verbal and written communication skills as reflected in effective presentations at meetings and a demonstrated strong publication record.
- Initiative and interpersonal skills with desire and ability to work in a collaborative, multidisciplinary team environment.
Desired Qualifications
- Experience in alloy design.
- Experience with machine learning methods and/or uncertainty quantification and propagation.
- Experience in crystal plasticity / solid mechanics constitutive modeling and/or density functional theory and/or molecular dynamics.

Pre-Employment Drug Test:  External applicant(s) selected for this position will be required to pass a post-offer, pre-employment drug test.  This includes testing for use of marijuana as Federal Law applies to us as a Federal Contractor.

Security Clearance:  This position requires a Department of Energy (DOE) Q-level clearance.

If you are selected, we will initiate a Federal background investigation to determine if you meet eligibility requirements for access to classified information or matter. In addition, all L or Q cleared employees are subject to random drug testing.  Q-level clearance requires U.S. citizenship.  If you hold multiple citizenships (U.S. and another country), you may be required to renounce your non-U.S. citizenship before a DOE L or Q clearance will be processed/granted.  For additional information, please see DOE Order 472.2

Note:   This is a two year Postdoctoral appointment with the possibility of extension to a maximum of three years.  Eligible candidates are those who have been awarded a PhD at time of hire date.

About Us

Lawrence Livermore National Laboratory (LLNL), located in the San Francisco Bay Area (East Bay), is a premier applied science laboratory that is part of the National Nuclear Security Administration (NNSA) within the Department of Energy (DOE).  LLNL's mission is strengthening national security by developing and applying cutting-edge science, technology, and engineering that respond with vision, quality, integrity, and technical excellence to scientific issues of national importance.  The Laboratory has a current annual budget of about $2.3 billion, employing approximately 6,900 employees.

 

LLNL is an affirmative action/ equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, marital status, national origin, ancestry, sex, sexual orientation, gender identity, disability, medical condition, protected veteran status, age, citizenship, or any other characteristic protected by law.