Phase Transformations Committee

Technical Programming

2018 TMS Annual Meeting & Exhibition: Additive Manufacturing of Metals: Establishing Location Specific, Processing-Microstructure-Property-Relationships III: Organized by Eric Lass; Mark Stoudt; Judith Schneider; Lee Semiatin; Behrang Poorganji; Clay Houser

Advances in additive manufacturing (AM) technology have created the ability to design and construct components with geometries and properties that cannot be achieved through traditional solidification and deformation processes. This ability has promoted multiple new design strategies whose success relies on close integration of engineering and materials science. An additional attractive aspect of additive processing is the ability to custom design specific properties within the component by layering, thereby promoting different microstructures or compositions (e.g., functionally-graded materials). However, the repetitive rapid solidification that occurs during AM also creates microstructures that deviate significantly from those observed in wrought materials with the same nominal composition. The result is a segregated microstructure with significant variations in local composition/phases, and, in some cases, life-limiting defects that are typically absent in wrought alloys. Most of the AM research currently focuses on refining the build process and on minimizing the residual stresses generated during the build. Consequently, there is far less emphasis on post-build heat treatments that homogenize the as-built microstructures and promote similar properties to wrought alloys. The main objective of this symposium is to develop a better understanding of the input-material requirements, process capabilities, and the resultant effects on finished product microstructure, texture, and properties. Research that elucidates the process-structure-property-performance relationships resulting from rapid solidification and transient phase transformations is essential. Information regarding the influence of inherent defects on the performance of AM-produced components is also greatly needed. Abstracts are requested that relate transient phenomena, recrystallization, transformation, and rapid solidification to additive manufacturing and its influence on phases, microstructure, and properties. Technical sessions emphasizing the following specific topics are planned: • Microstructure evolution in aluminum alloys, stainless steels and aerospace alloys (e.g., Ti, Ni alloys) • Texture measurements and control in AM parts • Defects and their effect on post-build (service) properties • Residual stress evolution and control • Novel applications, complex geometries fabricated via AM • Modeling of AM processes (including liquid and solid-state phase transformation behavior) • Emerging AM processes

2018 TMS Annual Meeting & Exhibition: Algorithm Development in Materials Science and Engineering : Organized by Mohsen Asle Zaeem; Mark Tschopp; Jonathan Zimmerman; Ebrahim Asadi; Mark Horstemeyer

As computational approaches to study the science and engineering of materials becomes more vital, it is critical to develop and improve techniques and algorithms that leverage ever-expanding computational resources. These algorithms can impact areas such as: data acquisition and analysis from sophisticated microscopes and other types of laboratory equipment, analysis and extraction of critical quantitative metrics from numerical simulations of materials behavior, and the ability to leverage specific computer architectures for revolutionary improvements in simulation analysis time, power, and capability. This symposium solicits abstract submissions from researchers who are developing new algorithms and/or designing new methods for performing computational research in materials science and engineering. Session topics include, but are not limited to: - Advancements that enhance modeling and simulation techniques such as density functional theory, molecular dynamics, Monte Carlo simulation, dislocation dynamics, phase-field modeling, and finite element analysis, - New techniques for simulating the complex behavior of materials at different length and time scales, - Computational methods for analyzing results from simulations of materials phenomena, and - Approaches for data mining, machine learning, high throughput databases, and extracting useful information from large data sets of numerical results.

2018 TMS Annual Meeting & Exhibition: Atom Probe Tomography for Advanced Characterization of Metals, Minerals and Materials: Organized by Haiming Wen; Simon Ringer; Gregory Thompson; Arun Devaraj; Keith Knipling; Gang Sha; David Seidman; Chantal Sudbrack

Atom probe tomography (APT), is an emergent characterization technique that is capable of determining the chemical identity of each individual atom and generating 3D chemical maps imaging the distribution of individual atoms. The technique offers high spatial resolution (better than 0.3 nm achievable in all directions) and high analytical sensitivity (as good as 1 appm). APT provides information on elemental composition of the specimen, 3D visualization of distribution of atoms, composition of phases, morphology and size of precipitates, and solute distribution across interfaces, at grain boundaries and along dislocations. In many APT analyses, crystallographic information has been retained within the data, with the potential to directly relate the composition of specific microstructural features to their crystallography with unprecedented sensitivity and resolution. APT can be utilized in many different fields for advanced imaging and analysis of metals, minerals and materials, despite some limitations. This symposium is designed to bring together scientists, engineers and technicians from across disciplines to discuss the technique of APT, its applications and limitations. The symposium will encompass research and applications spanning a wide variety of topics. Presentations on experimental, theoretical, and modeling research are solicited. Topics for this symposium include, but are not limited to:  Applications of APT in advanced characterization of metals, minerals and materials  3D reconstruction and data analysis  Impact of specimen and instrument parameters and optimization of acquisition conditions  Specimen preparation techniques  Limitations of APT  Progress in APT technique  Correlative techniques

2018 TMS Annual Meeting & Exhibition: Coupling Advanced Characterization and Modeling Tools for Understanding Fundamental Phase Transformation Mechanisms: An MPMD Symposium in Honor of Hamish Fraser: Organized by Gregory Thompson; Sudarsanam Babu; Peter Collins; Soumya Nag; Rajarshi Banerjee

In celebration of Professor Hamish Fraser’s 70th birthday and his career-long achievements in the fields of phase transformations, microstructure-structure property relationships, and advanced electron microscopy, this symposium aims to bring together experts in each area to address current and developing topics in these respective fields. The symposium of invited talks will cover a broad spectrum of advanced characterization and modeling tools that are available today which are being employed for addressing fundamental phase transformation mechanisms. In particular, the symposium will have dedicated sessions that emphasize phase transformations in non-ferrous alloys, such as Ti-base alloys and intermetallics, areas in which Prof. Fraser has made pioneering contributions. Other sessions will address phase transformation issues at different length scales, both in bulk and in nanostructured materials, and the use of advanced electron microscopy to reveal the underlying mechanisms of phase stability and transformation pathways in these materials.

2018 TMS Annual Meeting & Exhibition: Phase Transformation Across Multiscale Material Interfaces: Organized by Soumya Nag; Sudarsanam Babu; Gregory Thompson; Mohsen Asle Zaeem; Niyanth Sridharan

Interfaces play an important role in determining several properties in multiphase systems. In a materials system, interfaces can be present across different length scales, some examples being: (i) Nanoscale interphase interfaces in a precipitation hardened system, (ii) Microscale interface across ceramic on metal or metal on metal builds; for example bond coat deposition on turbine blade, multilayer thin films and (iii) Macroscale interfaces of joined similar or dissimilar materials; for example in brazing and soldering, transient liquid phase bonding, Diffusive phase transitions across these metastable interfaces can be triggered via thermo-mechanical processing so as to achieve close to equilibrium structural/compositional/stress states. Renditions of time-dependent development of off-equilibrium interface structures have been accomplished through multiscale experimental and computational techniques that allow for identification of the positions of atomic columns and structural defects at the interface. The motivation of this symposium is to bring together such novel studies directed towards identifying phase transformation pathways across multiscale material interfaces.

2018 TMS Annual Meeting & Exhibition: Phase Transformations and Microstructural Evolution : Organized by Gregory Thompson; Mark Aindow; Sudarsanam Babu; Rajarshi Banerjee; Tushar Borkar; Hai Chen; Paul Gibbs; Peeyush Nandwana; Ashwin Shahani; Yufeng Zheng

Phase transformation is still one of the most effective and efficient means to produce desired microstructures in materials for various applications. This symposium is a continuation in a series of annual TMS symposia focusing on phase transformations and microstructural evolution in materials during processing and in service. It intends to bring together theoretical, experimental and computational experts to assess the current status of theories of phase transformations and microstructure evolution primarily in the solid states. In addition to fundamental understanding of the mechanisms underlying phase transformations and microstructure evolution; attention will also be given to the utilization of unique transformation pathways to develop novel microstructures for advanced structural and functional materials.

2017 TMS Annual Meeting & Exhibition: Advanced High-Strength Steels: Organized by Tilmann Hickel; Wolfgang Bleck; Amy Clarke; Young-Kook Lee; Matthias Militzer

Advanced high-strength steels aim at improved properties by tailoring microstructures and processing. Three trends are of major interest nowadays in materials development activities: the decrease of structural length-scales of microstructural constituents like precipitates toward nanosized dimensions, the increase in alloying and consequently the interaction of different elements in localized zones, and finally more complex and adjusted robust processes activating several metallurgical mechanisms for adaptive microstructure development. This symposium invites studies on the control of process thermodynamics and kinetics for multiphase microstructures and the microstructure-property relationships of advanced high-strength steels. New design methods, including both advanced simulation methods and novel experimental strategies, are welcome. On the theoretical side, the various steps required for integrated computational materials engineering (ICME), with a particular focus on ab initio methods, computational thermodynamics and constitutive laws, will be discussed. The focus on the experimental side will be on characterization tools that support these approaches on all length- and time-scales, with a particular focus on the nanoscale. The symposium aims at an improved understanding of (i) hardening mechanisms, such as transformation and twinning induced plasticity, shear-band formation, solid solution and precipitation hardening; (ii) interface dominated processes, such as complexions at phase boundaries and segregation processes to grain boundaries; as well as (iii) failure mechanisms, such as crack formation and hydrogen embrittlement. New design concepts like damage tolerance and self-healing behaviour will be covered as well.

2017 TMS Annual Meeting & Exhibition: Gamma (FCC)/Gamma-Prime (L12) Co-Based Superalloys II: Organized by Eric Lass; Qiang Feng; Alessandro Moturra; Chantal Sudbrack; Michael Titus; Wei Xiong

The first report of a stable \\947;’-L12 phase in the ternary Co-Al-W system in 2006 has given rise to significant research on a new class of precipitation strengthened alloys, analogous to Ni-based superalloys, which are most often utilized in high temperature turbine engine components. These materials exhibit a yield stress anomaly similar to their Ni-based counterparts, where the yield strength increases with temperature, demonstrate promising high temperature flow stress behavior and creep resistance, outstanding wear resistance, and potentially better castability. However, some challenges still exist in the development of future industrially relevant Co-based \\947;’ strengthened alloys, including increasing \\947;’ solvus temperature, improving environmental resistance, and decreasing component weight critical to many turbine engine applications. This symposium continues in the tradition of the first TMS symposium on \\947;-\\947;’ Co-based superalloys held in 2014, and will bring together the growing community of researchers involved with further understanding and developing \\947;’ strengthened Co-based superalloys for high temperature and other applications. Experimental and computational investigations on Co- and Co-Ni-based alloys that focus on understanding materials response, use ICME-based approaches, and aid in rapid alloy development will be highlighted. Topics of interest include: strategies for increasing the \\947;’ solvus temperature, improving environmental resistance, evaluating high temperature mechanical performance, assessing phase stability and phase transformation mechanisms, and advancing processing methods of these promising new materials.

2017 TMS Annual Meeting & Exhibition: Materials by Design: An MPMD Symposium Honoring Greg Olson on the Occasion of His 70th Birthday: Organized by Carelyn Campbell; Michele Manuel; Wei Xiong; Jason Sebastian

The foundation of computational materials design and integration of computational materials engineering (ICME) have been pioneered by Professor Greg Olson over the last thirty years. Professor Olson has successfully demonstrated the use of a systems design approach for designing new materials by calculating optimum composition and processing routes to achieve desired materials properties. This approach has dramatically reduce the time and cost of the alloy development process. This symposium is dedicated to Professor Olson on the occasion of his 70th birthday. The scope of this invitational only symposium of includes the following: • Martensitic transformations • Transformation induced plasticity and its application to ductility and fracture toughness • Kinetics of coupled diffusional/displacive transformations • Electronic basis of embrittlement mechanisms in metals • Structure-property relations • Applications of high resolution microanalysis This symposium is invitation-only.

2017 TMS Annual Meeting & Exhibition: Phase Transformations and Microstructural Evolution: Organized by Gregory Thompson; Rajarshi Banerjee; Sudarsanam Babu; Deep Choudhuri; Raju Ramanujan; Monica Kapoor

Phase transformation is still one of the most effective and efficient means to produce desired microstructures in materials for various applications. This symposium is the third in a series of annual TMS symposia focusing on phase transformations and microstructural evolution in materials during processing and in service. It intends to bring together theoretical, experimental and computational experts to assess the current status of theories of phase transformations and microstructure evolution in solid states. In addition to fundamental understanding of the mechanisms underlying phase transformations and microstructure evolution, attention will also be given to the utilization of unique transformation pathways to develop novel microstructures for advanced structural and functional materials. Topics of choice for this year include, but are not limited to: *Phase stability and transformations in High Entropy/Complex Concentrated Alloys *Phase Transformations in Magnetic Materials *Phase transformations during Additive Manufacturing of Metals and Alloys *Phase transformations involved in Shape Memory Alloys

2017 TMS Annual Meeting & Exhibition: Solid State Precipitation: Organized by Seth Imhoff; Robert Hackenberg; Gregory Thompson

Our knowledge of precipitation from the solid state dates back to the discovery of age hardening in Al-Cu alloys. In the intervening century many contributions have been made to explore the thermodynamic and kinetic drivers of these reactions and the resulting morphology. This symposium will explore recent progress toward understanding this fundamental type of phase transformation. The scope includes experimental, theoretical, and modeling studies of diffusion-controlled precipitation and other phase-separation reactions. Example subject archetypes could include progressive metastable reactions, spinodal decomposition or clustering phenomena which may precede more conventional precipitation mechanisms.

2016 TMS Annual Meeting & Exhibition: Phase Transformations and Microstructural Evolution: Organized by Sudarsanam Babu; Dhriti Bhattacharyya; Yunzhi Wang; Osman Anderoglu; Juan P. Escobedo-Diaz; Jessica Krogstad; Long Qing Chen; Monica Kapoor; Amy Clarke; Gregory Thompson

Phase transformation is still one of the most effective and efficient means to produce desired microstructures in materials for various applications. This symposium is the fourth in a series of annual TMS symposia focusing on phase transformations and microstructural evolution in materials during processing and in service. It intends to bring together theoretical, experimental and computational experts to assess the current status of theories of phase transformations and microstructure evolution in solid states. In addition to fundamental understanding of the mechanisms underlying phase transformations and microstructure evolution, such as interface related effects, attention will also be given to the utilization of unique transformation pathways to develop novel microstructures for advanced structural and functional materials. Examples of studying these transformation kinetics and microstructure evolution behaviors through novel in-situ and ex-situ characterization techniques are sought. Our signature sessions within our symposium this year include (i) Phase transformations and microstructure evolution under extreme environmental conditions and (ii) Multiferroics and thermoelectric materials. The former topic may include such conditions as irradiation by high energy particles (both ions and neutrons); shock loading via high velocity impact; processing via Additive Manufacturing and/or other unique or severe thermo-mechanical cycling processes; and extremes in high or low temperatures. Beyond our signature sessions, we encourage abstracts related to but not limited to phase transformations in steels and ferrous alloys, non-ferrous alloys, ceramics, and other materials.

2016 TMS Annual Meeting & Exhibition: Phase Transformations in Multi-component Systems: An MPMD Symposium Honoring Gary R. Purdy: Organized by Hatem Zurob; Annika Borgenstam; Tadashi Furuhara; Wenzheng Zhang; Christopher Hutchinson; Robert Hackenberg

The modern materials for automotive, energy and construction applications upon which modern societies depend, all rely on the understanding of phase transformations in alloy systems. It is to this area that Professor Gary R. Purdy has made seminal contributions over a dedicated period of more than 50 years. This symposium is dedicated to Professor Gary R. Purdy on the occasion of his 80th birthday. The scope of symposium reflects his interests in phase transformations and microstructure evolution in multi-component systems. The topics covered will include: • Equilibrium and dynamic properties of interfaces with special emphasis on the phenomena of segregation, contact conditions at migrating interfaces, free energy dissipation at the interface and deviations from local-equilibrium. • Interface Structure and application of O-lattice theory. • Diffusion-induced Boundary Migration and Cellular Precipitation. • Modelling of phase transformation kinetics.

2015 TMS Annual Meeting & Exhibition: Phase Transformations and Microstructural Evolution: Organized by Sudarsanam Suresh Babu; Soumya Nag; Rajarshi Banerjee; Gregory Thompson; Amy Clarke; Frederic Danoix; Emmanuelle Marquis

Phase transformation is still one of the most effective and efficient means to produce desired microstructures in materials for various applications. This symposium is the third in a series of annual TMS symposia focusing on phase transformations and microstructural evolution in materials during processing and in service. It intends to bring together theoretical, experimental and computational experts to assess the current status of theories of phase transformations and microstructure evolution in solid states. In addition to fundamental understanding of the mechanisms underlying phase transformations and microstructure evolution, attention will also be given to the utilization of unique transformation pathways to develop novel microstructures for advanced structural and functional materials. The topics of choice for this year include, but are not limited to: -New insights into solid-solid phase transformations by coupling atom probe tomography (APT) with other experimental and computational tools. APT is a powerful technique for quantifying atomic scale, local element concentrations at interfaces in thin surface and multilayered films and a wide range of metallic, semiconducting, and hybrid/composite materials. APT, when coupled with information obtained by other powerful characterization techniques such as electron microscopy and spectroscopy, has lead to novel insights into the fundamental mechanisms associated with solid-solid phase transformations. While some mechanistic insights have been discussed and recorded in seminal peer-reviewed publications, previously available experimental tools did not usually afford the ability to discern these mechanisms at the atomistic scale. The motivation is to bring together multiple groups of researchers coupling atom probe tomography with other experimental and computational tools to discuss exciting advancements in understanding solid-solid phase transformation mechanisms. -Iron-chromium alloys are the basis for stainless steels, making their characterization essential for understanding the evolution of stainless steels. The study of iron-chromium based alloy microstructures and their influence on properties (in particular, mechanical and corrosion resistance) has been an active field for nearly a century, but modern experimental and numerical techniques (and their combinations) have recently brought important new insights into this field. This session aims to bring together scientists studying iron-chromium alloys with experimental (APT; M�ssbauer spectroscopy; Small Angle Neutron Scattering....) and/or a modeling (classical thermodynamics; Ab-Initio, Molecular Dynamics, Monte Carlo & Phase Field modeling) approaches. The fundamental understanding of pair interaction functions, nucleation and growth versus spinodal decomposition, and segregation to grain boundaries, for example, and consequences on properties (e.g. mechanical behavior, radiation sensitivity, and corrosion resistance) are of interest. Investigations that utilize both experimental and modeling approaches are highly encouraged.