Nanomechanical Materials Behavior Committee

Technical Programming

2019 TMS Annual Meeting & Exhibition: Fracture Processes of Thin Films and Nanomaterials: Organized by Daniel Kiener; Megan Cordill; Johannes Ast; Brad Boyce

This symposium will focus on recent developments in the field of fracture of thin films and small volumes, focusing on the uncovering the mechanisms responsible for improved properties. Such novel insights are enabled by advanced testing technologies paired with comprehensive characterization at the nanoscale and a suited fracture-mechanical analysis. With the wide variety of applications (semiconductors, printed electronics, energy storage, protective coatings, etc.) and the required control of structural and functional properties, a better understanding of the relationship between processing, microstructures, and failure mechanisms is required to design more robust and reliable devices and structures for use in any environment. The deformation characteristics of thin films and small volumes have been explored for years using different in-situ and ex-situ techniques (nanoindentation, TEM, SEM, micro-XRD, etc). However, the need for examination of local fracture processes calls for dedicated testing techniques that permit high temporal and local resolution of structural and mechanical properties, ideally coupled with measurements of electrical or thermal characteristics under applied load. Furthermore, the enhanced understanding of the impact of interface design on fracture in thin films and nanostructured materials is of interest. The combination of advanced testing techniques with adapted fracture mechanics evaluation concepts will enable a safe design of future components based on thin films and small volumes. The subject areas of the symposium include, but are not limited to: • Local analysis of stress and strain around crack tips • Fracture of nanostructured materials (thin films, printed structures, nanocrystalline materials, …) • Developments in nanoporous materials for energy harvesting or storage applications • Fracture concepts to analyze miniaturized volumes and bridge scales to macroscopic properties • New developments in fracture testing techniques using coupled in-situ measurements (electrical, optical, mechanical, etc.) or in enhanced environments (high temperatures, humidity controlled, etc.) A joined session on fracture in harsh environments (symposium ‘Micro- and nanomechanical testing in harsh environments’) is planned.

2019 TMS Annual Meeting & Exhibition: Mechanical Behavior Related to Interface Physics III: Organized by Jason Trelewicz; Nathan Mara; Erica Lilleodden; Siddhartha Pathak; Jordan Weaver; Marc Legros

Interfaces constitute a key microstructural variable for tuning materials behavior across a wide range of length scales from nano to macro in single and multiphase systems. The advent of novel multi-phase/multi-interface nanomaterials holds great potential for enabling unparalleled performance under coupled extremes. Interfaces often dominate the material response in nanostructured systems and produce unique combinations of properties that derive from the physics of grain boundaries, phase boundaries, and/or surfaces. A fundamental understanding of interfacial physics and coupled phenomena impacting mechanical behavior is thus needed to harness new concepts and methodologies in interface design for multifunctional performance. This symposium aims to discuss interface physics that govern mechanical behavior and coupled phenomena in interfacially-driven multifunctionality in both single and multiphase materials. Talks are solicited that cover fabrication, characterization, and modeling of materials with deliberately designed interfaces with particular emphasis on new insights into fundamental mechanisms, analysis of defects, and their implications for multifunctional performance. Abstracts on recent developments in mechanical testing techniques (e.g., in situ straining in TEM, micropillar testing, etc) and in high-fidelity modeling techniques (e.g., ab initio, molecular dynamics, etc) are also solicited. Topics of interest include, but are not necessarily limited to: -Influence of interface structure and chemistry on deformation mechanisms -Mechanical behavior of low dimensional materials (e.g., thin films, nanowires, nanotubes, and nanoparticles) -Physics of phase boundaries in multiphase systems, such as crystalline-amorphous composites, nanolaminates, nanoparticle/matrix composites, and nanoporous materials -Mechanical behavior of grain boundary engineered nanomaterials (e.g. solute stabilization, grain boundary complexion formation, duplex and gradient nanostructures) -Micro, meso, and macroscale modeling of deformation processes and coupled phenomena as they relate to interface physics -In situ testing methodologies for investigating mechanical behavior and coupled extremes such as mechanical and irradiation of small volumes of material

2019 TMS Annual Meeting & Exhibition: Micro- and Nanomechanical Testing in Harsh Environments: Organized by Verena Maier-Kiener; Sandra Korte-Kerzel; Peter Hosemann; Afrooz Barnoush; Jeffrey Wheeler; Dhriti Bhattacharyya

Most materials are exposed to an environment different than that found in laboratory conditions, and it has been recognized that a material’s properties change based on the environment to which it is exposed. Therefore, understanding the mechanisms by which a material’s properties change in harsh environments (e.g. high and low temperatures, high strain rate deformation, and corrosive agents) and under non-ambient conditions is key to understanding materials behavior in service conditions. Micro- and nanoscale materials testing has been often utilized for a deeper understanding of the basic phenomena of materials degradation and behavior. An obvious next step is to expand these valuable measurements to the environments that materials are exposed to during service conditions in order to study the synergistic effects between harsh environments and materials property degradation on the nanoscale. The harsh environments materials experience can have a direct impact on the performance of nano-devices and nano-enabled energy systems in many different applications. Topics include: - Nanoindentation and micromechanical testing at non-ambient conditions - Small scale mechanical behavior under harsh environments and/or dynamic loading conditions - New approaches for reliable testing at elevated and low temperatures - Accelerated testing techniques - In-situ electrochemical loading during micromechanical testing

2018 TMS Annual Meeting & Exhibition: Fracture: 65 Years after the Weibull Distribution and the Williams Singularity: Organized by Brad Boyce; Ellen Cerreta; Jacob Hochhalter; Jonathan Zimmerman

In 1951, Waloddi Weibull published a single-author paper describing a new statistical distribution “of wide applicability” in the Journal of Applied Mechanics. The very next year in the same journal, Max Williams published a single-author paper describing an analytic stress singularity that has become the foundation of linear elastic fracture mechanics. The Weibull distribution provides a stress-based method for assessing the statistics of failure whereas the Williams singularity provides a deterministic description of the stress field at a crack tip that drives fracture. While the two approaches are quite different, they both continue to be profoundly useful for engineering design. The symposium will focus on application of these methods to materials science, the limitations of these methods and nuance that has been unearthed after 65 years of use. How have these methods assisted in the development of improved engineering materials and more reliable engineered structures? What recent analysis methods for material failure might have a similar impact 65 years from now? Why is recent research not as readily adopted by broad engineering practice? What are the current generational challenges in fracture and material failure?

2018 TMS Annual Meeting & Exhibition: Mechanical Behavior at the Nanoscale IV: Organized by Christopher Weinberger; Qian Yu; Garritt Tucker; Nan Li; Yu Zou; Jonathan Zimmerman; Scott Mao

Understanding the mechanics of materials in small volumes is of fundamental importance because it simultaneously allows for the exploration of new properties at the smallest of length scales as well as provides a basis for understanding multiscale phenomena that originate at these lengthscales. This symposium will focus on the mechanical properties of small-volume and low-dimensional materials, as well as bulk materials that are comprised of or are aggregates of these materials including bulk nanostructured materials and nanoscale based heirarchical materials. Of particular interest are studies that discuss sample size effects, applications of nanoscale mechanical testing and the associated characterization, as well as modeling that addresses the mechanical properties of these materials. Properties of interest include, but are not limited to: elasticity, strength, plastic flow, fatigue, and fracture with material systems ranging from hard materials, including metals and ceramics, to soft and biological materials. Topics will include: - Size effects on elasticity, strength, plastic flow, fracture and fatigue in low dimensional materials including nanopillars, nanowires, nanoparticles, thin films, multilayered materials, graded materials, and architecture-designed materials. - Changes in deformation types or patterns due to changes in scale including those due to size affected phase transformations, changes in density and types of interfaces, as well as available deformation sources. - Ex-situ and in-situ (SEM, TEM, XRD, neutron, etc.) mechanical characterization methods. - Modeling and simulation at all scales, as well as coupled scale modeling, of mechanical behavior of nanostructured materials - Confinement and size effects in glasses and disordered media. - Small scale mechanics of soft matter: polymers, and biomaterials (e.g collagen, chitin, and keratin, as well as other organic materials).

2018 TMS Annual Meeting & Exhibition: Ultrafine-grained Materials X: Organized by Suveen Mathaudhu; Irene Beyerlein; Avinash Dongare; Chong Soo Lee; Terry Lowe; Srikanth Patala; Lee Semiatin; Jason Trelewicz; Janelle Wharry; Caizhi Zhou

This is the tenth international symposium that focuses on all aspects of the science and technology of ultrafine grained (UFG) and nanocrystalline materials. This symposium covers a broad scope, ranging from fundamental science to applications of bulk ultrafine-grained (grain size <1000 nm) and nanostructured (feature size <100 nm) materials. It provides a forum on the topics of fabrication and understanding of UFG and nanocrystalline materials including conventional and emerging technologies and advancements, fundamental issues in severe plastic deformation (SPD) processing and SPD-processed materials, UFG and nanocrystalline microstructure evolution, mechanical and physical properties, deformation mechanisms, superplasticity, joining and bonding, computational and analytical modeling, structural and functional applications, etc. Other emerging topics to be covered include gradient and layered nanostructures, vapor-phase processing, powder processing, rapid-solidification methods, bio-inspired nanomaterials, and radiation tolerant nanomaterials. Also, in honor of the 10th iteration of this symposium, we will hold a “Pioneers of Ultrafine Grained Materials” session that will highlight the contributions of the superheroes of this field. Awards: UFG X will be hosting a Young Scientist Session for students or post-docs within three years of receiving their Ph.D. There will be up to two Gold Medals and three Silver Medals for best oral presentation. Awards will also be given for best poster (One Gold Medal and two Silver Medals). A committee that includes the symposium organizers and invited speakers will decide the awards. Each medalist will receive a certificate, and may receive a cash prize, depending on resources available.