About

Michael Falk is a professor of materials science and engineering, mechanical engineering, and physics at Johns Hopkins University. He serves as the vice dean for undergraduate education within the Whiting School of Engineering, a position he has held since July 2017. Falk’s research focuses on utilizing computer simulation on the atomic scale to understand what happens when materials are pushed out of equilibrium by processes such as bending, breaking, charging, and undergoing frictional sliding. Since returning to Johns Hopkins, his funded projects have expanded to include educational research on how engineering students best learn computing and two NSF-funded partnerships with Baltimore City Schools to increase engagement of students, teachers, and communities in STEM learning. Falk has also been a strong advocate for diversity, particularly creating a welcoming climate for LGBTQ people within the university and the engineering and physics professions.

Research topics

• Composite material
• Chemical physics
• Crystallography
• Materials science
• Thermodynamics

Selected publications

• Primary defect production from molecular dynamics simulations of high-energy displacement cascades in NbMoTaW alloys

  Physical Review Materials · 2026-02-09

  articleOpen access

  In this work, we report on large-scale molecular-dynamics (MD) simulations of displacement cascades in equiatomic NbMoTaW alloys at PKA energies ranging from 0.15 to 150 keV. We find defect production to be strongly dependent on recoil energy, scaling sublinearly up to 10 keV, and linearly thereafter. We find the sublinear regime to be defined by low values of surviving Frenkel pairs, typically found as isolated point defects or small defect clusters, while at higher recoil energies dense cascades become more frequent, leading to splitting into subcascades and the production of relatively large prismatic-dislocation loops with <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mrow> <a:mo>〈</a:mo> <a:mn>111</a:mn> <a:mo>〉</a:mo> </a:mrow> </a:math> and <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"> <b:mrow> <b:mo>〈</b:mo> <b:mn>001</b:mn> <b:mo>〉</b:mo> </b:mrow> </b:math> Burgers vectors. These loops immobilize large fractions of defects, leading to a rapid growth of the number of surviving defects in the linear regime. We also anneal post-cascade defect configurations using object-kinetic Monte Carlo (OKMC) simulations to account for intracascade recombination on time scales not accessible to MD simulations. Cascade annealing is strongly temperature dependent, with the OKMC simulations only showing significant recovery at 1000 K but not below. Our results are in general agreement with existing published data for refractory concentrated alloys.

  PublisherDOI

• Quantifying the Features of an Amorphous Solid's Local Yield Surface

  ArXiv.org · 2026-03-04

  articleOpen accessSenior author

  In two-dimensional Lennard-Jones glasses, mechanical probing reveals that local yield surfaces are dominated by regions with a positive second derivative of the yield stress with respect to the loading angle. Each feature corresponds to a shear transformation zone and a characteristic non-affine displacement field at yield. Most features are well described by a combined Schmid-Mohr-Coulomb criterion parameterized by a weak-plane orientation, a critical stress, and a pressure sensitivity. The resulting parameter statistics clarify how the onset of plastic flow is governed by the population of discrete yielding features encoded in the amorphous structure.

  PublisherOA PDF

• Topological Defects in Amorphous Solids

  arXiv (Cornell University) · 2026-04-08

  articleOpen access

  Topological defects (TDs) are crucial for understanding important physical properties of crystalline materials including mechanical failure, ion transport, and two-dimensional melting. This concept has not translated to disordered materials like glasses because these solids have no obvious reference structure that can be used to define TDs. As a result, key properties related to those listed above have typically been modeled using purely phenomenological approaches. Recent studies have demonstrated that certain observables commonly associated with TDs can also be identified in disordered solids indicating that topological concepts may be as crucial in amorphous solids as in crystals. This hints that TDs may offer a first-principles framework for understanding their mechanical response and complex spatiotemporal dynamics. In this Perspective, we review recent theoretical, numerical, and experimental studies that have exploited topological concepts to rationalize mechanical properties of amorphous solids. We also highlight pressing open questions and some promising directions for future research in the field.

  PublisherOA PDF

• Topological Defects in Amorphous Solids

  arXiv (Cornell University) · 2026-04-08

  preprintOpen access

  Topological defects (TDs) are crucial for understanding important physical properties of crystalline materials including mechanical failure, ion transport, and two-dimensional melting. This concept has not translated to disordered materials like glasses because these solids have no obvious reference structure that can be used to define TDs. As a result, key properties related to those listed above have typically been modeled using purely phenomenological approaches. Recent studies have demonstrated that certain observables commonly associated with TDs can also be identified in disordered solids indicating that topological concepts may be as crucial in amorphous solids as in crystals. This hints that TDs may offer a first-principles framework for understanding their mechanical response and complex spatiotemporal dynamics. In this Perspective, we review recent theoretical, numerical, and experimental studies that have exploited topological concepts to rationalize mechanical properties of amorphous solids. We also highlight pressing open questions and some promising directions for future research in the field.

  PublisherDOI

• Quantifying the Features of an Amorphous Solid's Local Yield Surface

  arXiv (Cornell University) · 2026-03-04

  preprintOpen accessSenior author

  In two-dimensional Lennard-Jones glasses, mechanical probing reveals that local yield surfaces are dominated by regions with a positive second derivative of the yield stress with respect to the loading angle. Each feature corresponds to a shear transformation zone and a characteristic non-affine displacement field at yield. Most features are well described by a combined Schmid-Mohr-Coulomb criterion parameterized by a weak-plane orientation, a critical stress, and a pressure sensitivity. The resulting parameter statistics clarify how the onset of plastic flow is governed by the population of discrete yielding features encoded in the amorphous structure.

  PublisherDOI

• Chemical complexity enhances grain boundary absorption efficiency through expansion of microstate phase space

  Physical Review Materials · 2025-08-15 · 2 citations

  articleSenior author

  Grain boundaries (GB) are effective defect sinks and can be engineered to enhance radiation tolerance in materials. The capacity of a GB to absorb radiation damage is influenced by the material's ability to accommodate new atoms into its internal structure. This work provides a quantitative link between material composition and self-interstitial atom (SIA) absorption efficiency through GB structural rearrangements. Molecular dynamics simulations are employed to reveal GB evolution to denser structural units in a chemically complex alloy, whereas the GBs in a pure material and dilute alloy establish a steady structural state during the SIA deposition. Following, regions of structural transformation are correlated to large positive misfit volume differences and thus higher hydrostatic stress. This environment drives GB structural unit transformations to relieve stress and accommodate the absorbed defects. There is an additional driving force from chemistry which promotes structural transformations given nominally lower values of local stress. These regions are mostly rich in Co and Cr, which are also the regions where we observe more pronounced SIA absorption events. Energetically, we find that it is this balance of thermodynamics and mechanical stress which stabilizes specific GB structures. GBs in pure Ni, $\mathrm{N}{\mathrm{i}}_{95}\mathrm{C}{\mathrm{r}}_{5}$, and equiatomic CoCrNi are evaluated as a function of SIA deposition into the GB. We find that chemistry has an unequivocal role in widening the available microstate range for defect absorption, which highlights chemical tailoring as a pathway for enhanced radiation resistance due to elevated GB absorption efficiencies.

  PublisherDOI

• Role Model Videos featuring Minoritized Engineers (Resource Exchange)

  2025-08-21

  article
  PublisherDOI

• Metastable grain boundary sink behavior revealed through deep-learning image analysis

  Journal of Nuclear Materials · 2025-12-10

  article
  PublisherDOI

• Evaluation of a Hybrid Algebra-for-Engineering Program: Identifying Strengths, Challenges, Lessons Learned and “Fit” in an Urban Education Landscape (Evaluation, Diversity)

  2025-08-21 · 1 citations

  article
  PublisherDOI

• Designing Corrosion-Resistant CoCrNi Medium Entropy Alloys via Short-Range Order Modification

  ArXiv.org · 2025-06-11

  preprintOpen access

  Equiatomic CoCrNi medium entropy alloys are known for their unique properties linked to chemical short-range order (CSRO), crucial in both percolation processes and/or nucleation and growth processes influencing alloy passivation in aqueous environments. This study combines extended x-ray absorption fine structure, atomistic simulations, electrochemical methods, x-ray photoelectron spectroscopy, and transmission electron microscopy to explore CSRO evolution, passive film formation, as well as its characteristics in the as-homogenized CoCrNi condition, both before and after aging treatment. Results reveal a shift in local alloying element bonding environments post-aging, with simulations indicating increased Cr-Cr CSRO in 2nd nearest neighbor shells. Enhanced passive film formation kinetics and superior protection of the aged alloy in harsh acidified 3 mol/L NaCl solution indicate improved aqueous passivation correlated with Cr-Cr CSRO. This work establishes a direct connection between alloy CSRO and aqueous passivation in CoCrNi, highlighting its potential for tailored corrosion-resistant applications.

  PublisherOA PDFDOI

Recent grants

• STEM Achievement in Baltimore Elementary Schools (SABES)

  NSF · $7.4M · 2012–2018

• Baltimore Online Algebra for High School Students in Technology

  NSF · $2.4M · 2020–2026

• Fundamental Simulation Studies of Mixing at Sliding Interfaces

  NSF · $250k · 2005–2009

• Extended Time Scale Simulation Studies of Nanoscale Friction

  NSF · $280k · 2009–2013

• Collaborative Research: CDI-Type I: Meta-Codes for Computational Kinetics

  NSF · $280k · 2010–2014

Frequent coauthors

• Timothy P. Weihs

  Johns Hopkins University

  46 shared

• Sylvain Patinet

  37 shared

• Suhas Eswarappa Prameela

  American Institute of Aeronautics and Astronautics

  36 shared

• Alejandra J. Magana

  Bridge University

  28 shared

• Camilo Vieira

  Universidad del Norte

  25 shared

• Dwight J. Rouse

  Island Institute

  24 shared

• Peng Yi

  Chongqing Jiaotong University

  23 shared

• Michael Reese

  Chicago Council on Global Affairs

  21 shared

Education

• PhD, Physics

  University of California Santa Barbara

  1998

• MSE, Computer Science

  Johns Hopkins University

  1991

• BA, Physics

  Johns Hopkins University

  1990

Awards & honors

• ARPA-E CHADWICK Grant