Materials Science & Technology Conference 2018

Materials Science & Technology Conference 2018

Dates: October 14 – 18 2018

Place: Columbus, Ohio

 

Members who attended:

Professors:

Sneha Nerra, Adam Powell, Yu Zhong​, Danielle Cote, John Obayemi

Graduate Students

Yao Xu, Bryer Sousa, Caitlin Walde, Nima Rahbar, Shadi Darvish, Hooman Sabarou, Kyle Fitzpatrick-Schmidt, Jeremy Fedors, Derek Tsaknopoulos, Bryer Sousa

Awards Received:

Professor Richard D. Sisson, Jr:

Named Fellow of the American Ceramic Society (ACers)

Named Fellow of the International Federation for Heat Treatment and Surface Engineering (IFHTSE)

Professor Diana Lados:

Inducted as a Fellow of Alpha Sigma Mu

Incoming ASM Trustee

Chair of Awards Policy Committee

Mrs. Jessica A. Clinton

Former Chapter President Materials Advantage, WPI

ASM Emerging professional Achievement Award: The award was established in 2010 to recognize and honor extraordinary ASM volunteers who less senior individuals, i.e. 0 – 5 years of experience post-graduation, who have made a significant impact on ASM International through devoted service and dedication to the future of the Society.

Cesar Guerrero:

The 2018 William Park Woodside Founder’s Scholarship Winner

Established in 1996, by a gift from Mrs. Sue Woodside Shulec in honor of her grandfather, William Park Woodside. Mr. Woodside founded Steel Treaters Club more than 100 years ago and later served as president of ASM. The Scholarship has been established to encourage an ASM student member studying materials science and engineering at the junior or senior level who demonstrates strength in leadership, character, and academics. Full tuition of up to $10,000 for one academic year and a certificate of recognition are provided to the recipient.

 

Presentations:

New Heat Treatment Method to Manipulate the Structure of PMN-PT Single Crystals:

Hooman Sabarou,Vadym Drozd, Osama Awadallah, Andriy Durygin, Dehua,Yu Zhong

The research investigates the role of heat treatment under low oxygen partial pressure on structural and ferroelectric properties of a (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT) single crystal. The structural change has been examined by thermal analyses, high temperature Raman spectroscopy, and in situ XRD. Based on preliminary results, a heat treatment under low oxygen partial pressure has been utilized. The investigations reveal that the heat treatment can modify oxygen bonding inside the sample and leave an impact on its phase transition sequence. Impedance measurements prove that these structural changes come along with changes in ferroelectric properties. They can either promote or inhibit the formation of ferroelectric phases. The study explains how oxygen partial pressure plays a key role in this phenomenon and what mechanisms are involved in. It is for first time that the approach of low temperature heat treatment under low oxygen partial pressure has been introduced for PMN-PT single crystals.

 

The Impact of Alloy Elements to the Secondary Phase Stabilities in Grade 91 Alloy:

Andrew Smith, Mohammad Asadikiya, Yu Zhong

Grade 91 (Gr.91) has recently been investigated quite extensively over the past few decades. Its properties that make them so useful in high temperature applications are by their high creep strength made through their secondary phases such as M23C6 and MX, that stabilize through heat treatment. However, one issue that arises from this alloy are type IV cracks propagated through the materials heat-affected-zone (HAZ) after welding. In previous research we applied a baseline study of Gr.91 by examining the stabilities of M23C6, MX, and Z-phase precipitates as well as examine the mechanisms that have been observed through previous short-term and long-term studies. In this study we will provide a clear understanding, through CALculation of PHAse Diagram (CALPHAD) approach, of what elements influences the stability of the secondary precipitates under lower Ac temperatures. This includes alloying elements such as manganese (Mn), nickel (Ni), and titanium (Ti) added to the baseline study.

P3-22: In-situ Manufacturing Techniques for Aluminum Matrix Nanocomposites:

Jeremy Fedors, Eunkyung Lee, Brajendra Mishra

Increasing the strength and stiffness of aluminum at elevated temperatures, around 230-300°C, is desirable for a multitude of applications, particularly for the lightweighting of automotive and aerospace cast components. One approach to achieving this is to disperse ceramic nanoparticles in the aluminum matrix, though effective and low-cost methods for doing so have not been demonstrated at an economical scale. Two promising processes to overcome this are the in-situ gas-liquid reaction (ISGR) and in-situ self-propagating high-temperature synthesis (SHS). AlN reinforcements from a nitrogen bubble reaction with aluminum are produced via ISGR, and TiC reinforcements from coarser Ti and C powders are produced via SHS, within aluminum melts. Updates to the progress of optimizing and scaling up nanocomposite production via these processes will be presented; as well as results of dilution of the nanocomposite material and ultrasonic dispersion of particles to allow for effective use in squeeze casting and high-pressure die casting.

In-vivo and Ex –vivo Studies of Biosynthesized Magnetic Nanoparticles for Specific Targeting of Triple Negative Breast Cancer:

John Obayemi, Jingjie Hu, Vanessa Uzonwanne, Ali Salifu, Karen Malatesta, Derek Adler, Edward Yurkow, Winston Soboyejo

The results of in-vitro and ex vivo studies of conjugated biosynthesized magnetite nanoparticles (BMNPs) are presented. These include studies of the specific targeting of triple negative breast cancer using ligand conjugated BMNPs. First, conjugated BMNPs are injected into athymic nude mice bearing MDA-MB-231 tumors subcutaneously to develop different stages of tumors. The mice are then sacrificed within the early, mid and late stages of tumor growth, to analyze the extent of nanoparticle attachments to the tumors. The presence of conjugated ligand (LHRH), whose receptors are overexpressed on the surfaces of breast cancer cells in the BMNPs, is shown to enhance the attachment of the BMNPs to TNBC cells/tissues at different stages of breast cancer. This is revealed via Prussian Blue staining, immunofluorescence staining, immunohistochemical staining, transmission electron microscopy and magnetic resonance imaging. The implications of the results work are also discussed for the specific targeting of triple negative breast cancer.

Bioinspired Design of Next Generation Structural and Thermal Materials:

Nima Rahbar

This talk focuses on the fundamental ideas arising from understanding the mechanisms behind the superior mechanical and thermal properties of biological materials through four specific examples of nacre, bamboo, and lipid bilayers. In nacre’s structure, the organic matrix, pillars and the roughness of the aragonite platelets play important roles. The highly nonlinear behavior is the result of distributed deformation in the nacre-like structure due to the existence of nano-asperities and nano-pillars with near theoretical strength. The unique properties of bamboo come from the natural composite structure of fibers that comprises mainly cellulose nanofibrils in a matrix of intertwined hemicellulose and lignin called lignin-carbohydrate complex. Here we have studied mechanical and fracture properties of bamboo at multiple scale. Lastly, given the amphiphilic nature and chemical structure, phospholipids were studied as inspiration for novel design thermal diodes. These results provide significant new insights into developing new thermal insulation for engineering applications.

The Thermodynamic Investigation of the Effect of CO2 to the Stability of (La0.8Sr0.2)0.98MnO3d and La0.6Sr0.4Co0.2Fe0.8O3d as Cathodes of Solid Oxide Fuel Cell:

Shadi Darvish, Yu Zhong

Thermodynamic predictions regarding the formation of secondary phases in CO2 containing atmosphere on the (La0.8Sr0.2)0.98MnO3δ (LSM-20)/ La0.6Sr0.4Co0.2Fe0.8O3 (LSCF-6428) surface and at the cathode/electrolite interface have been studied using the CALculation of Phase Diagram (CALPHAD) approach. The effects of temperature, CO2 partial pressure, O2 partial pressure and the cathode composition on formation of secondary phases have been investigated and correlated with the available experimental results found in the literature. Our study predicts that the SrCO3 has the possibility to form on the surface and at triple phase boundaries as a result of CO2 exposure to the system. In addition, it is indicated that the CO2 exposure does not change the electronic/ionic carriers’ concentration in perovskite phase. The observed electrical conductivity drop is predicted to occur due to the formation of secondary phases such as La2Zr2O7, SrZrO3 or SrCO3, at the cathode/electrolyte interface, resulting in the blocking of the electron/ion transfer paths.

Mapping of the Relationship between Melt Pool Geometry and Crystallographic Texture of Inconel 718 Deposited via Laser Powder Bed Fusion Process

Sneha Prabha Narra, Jack Beuth

Previous work by the authors has demonstrated the relationships between melt pool geometry and microstructure, emphasizing size scale of solidification microstructure for both electron and laser beam powder bed fusion processes. In this work, crystallographic texture in laser melted Inconel 718 is linked to melt pool geometry for direct application to microstructure control in laser powder bed fusion additive manufacturing (AM) processes. This is achieved via process knowledge-based design of experiments in which beam power, velocity, and hatch spacing are varied systematically. Resulting changes in melt pool geometry due to changes in processing parameters is associated with the grain growth and solidification conditions that result in distinct textures. The methods developed in this work to understand the relationships between melt pool geometry and texture can be extended to different powder bed fusion processes and materials.

 

Understanding Hot Cracking in Laser and Electron Beam Powder Bed Fusion of Al7075

Sneha Prabha Narra, Daming Ding, Shrivani Pandiya, Jack Beuth

In this work, hot cracking in high-strength aluminum alloy Al7075 was studied in laser and electron beam powder bed fusion additive manufacturing (AM) processes. This alloy is desired in the aerospace and automotive industries due to its high strength to weight ratio. However, it has not been a satisfactory alloy for AM fabrication of components due to its hot cracking sensitivity. Experiments ranging from simple single melt tracks to solid blocks were conducted to observe the hot cracking behavior. Finite element modeling is used to estimate the residual stresses and understand the crack growth. These trends were analyzed and mapped to obtain the optimum set of processing parameters that result in minimal hot cracking and enable the use of Al7075 in AM.

 

On Determining Stress-Strain Curves and the Fracture Toughness of Metal Feedstock Powder for Additive Manufacturing with Nanoscale Instrumented Indentation Testing

 Bryer Sousa, Derek Tsaknopoulos, Victor K. Champagne, Danielle Cote

While Metal Additive Manufacturing (MAM) develops, materials scientists and engineers will require a more mindful understanding of the mechanical, optical, and thermal properties of their feedstock powder. This need follows from the fact that acute inconsistencies in powder fabrication and powder preparation can cause dramatic behavioral discrepancies in subsequent MAM-made materials. Such effects are particularly exacerbated in materials fabricated by solid-state joining additive manufacturing. Though advances have been realized within the domain of systematizing the methodologies involved with thermal and optical characterization of MAM feedstock powder, noteworthy challenges have forbidden affordable and widely available standardized mechanical characterization approaches. In order to make necessary advancements in the microscopic mechanical characterization of metal powder particles, the case of extracting stress-strain curves of metal powder particles with nanoindentation, as well as our work in determining yield strength, fracture toughness, and more, is considered herein.

Optimizing Thermal Parameters for Powder Pre-Processing Treatments

Caitlin Walde ; Danielle Cote ; Richard Sisson ; Victor Champagne 

Research has shown that the chemistry and microstructural properties of the feedstock powder can significantly affect the properties of the consolidated material.  Thermal treatment and recycling parameters for powders used in both solid and liquid state processes can further affect the microstructure and properties of the consolidated parts. Understanding the powder microstructure and effects of powder pre-treatment can aid in optimizing the properties of the final consolidated part. This research proposes a method for the characterization and optimization of powder pre-processing thermal parameters using aluminum alloy powder as examples. Light microscopy, electron microscopy, and hardness were used to evaluate each condition.

 

Nanomechanically Supported Computational Modeling for Thermo-Mechanical Property Design and Optimization in Small-scale Powder Metallurgy

The use of trial-and-error practices in alloy design and processing adds substantial barriers impeding novel alloy qualification and adoption to market. However, with access to large sets of data, the cost of the trial-and-error method can be sidestepped by way of iteratively coupling computational models with supportive experimental testing, expediting the materials' design process. At present, Thermo-Calc – a computational thermodynamic and kinetic software – is combined with both static and dynamic nanoindentation and micro-particle compression testing in order to establish representative correlations for the case of alloyed aluminum powder. Through the developed techniques, comparisons of material properties (hardness, yield strength, fracture toughness, fatigue resistance, creep) for various conditions is enabled, such as differences in processing methods, alloy compositions, and post-processing heat treatments. The effectiveness of this work is determined using thermal, optical, and mechanical characterization methods.

Analysis of Aluminum Alloy Feedstock Powder used in Solid State Processing

Caitlin E. Walde, Danielle Cote, Richard Sisson, Victor Champagne

Gas-atomized metallic powders are commonly used as feedstock in certain solid state processes. Research has shown that the chemistry and microstructural properties of the feedstock powder significantly affect the properties of the consolidated material.  Understanding the powder characteristics before use in solid state processing can lead to optimization of properties of the final part.  Additionally, thermally treating powders prior to consolidation affects the characteristics and microstructural evolution of the powder. This work highlights thermal treatments for aluminum alloys, guided by thermodynamic and kinetic modeling. Light microscopy, electron microscopy, and hardness were used to evaluate each condition in both two- and three-dimensions.

Microstructural Evolution Simulation for Property Prediction in Cold Spray Processing

Danielle L. Cote, Victor Champagne, Jr.

The cold spray process is a dynamic powder consolidation technique capable of producing materials with high strength and toughness through an extremely versatile processing system. In this solid state additive manufacturing process, the consolidated material and mechanical properties are directly dependent on the powder properties. To account for this relationship, a through-process model was developed as a predictive tool to follow the microstructural evolution of the cold spray process – from as-received powder to post processing consolidated material. The significance of the feedstock powder properties becomes evident in this work and will be discussed in terms of kinetic, thermodynamic, and solidification predictive simulations and experimental characterization. The final model predicts material and mechanical properties of the consolidated material as a function of feedstock powder and process parameters.

Computational Thermodynamic and Kinetic Modeling for Phase Dissolution and Growth in Al Alloys

Kyle L. Fitzpatrick-Schmidt, Victor Champagne, Danielle Cote

Secondary phases can strongly influence the mechanical properties of a material. In this work, the dissolution of these phases is studied in aerospace aluminum alloys. Traditionally, experimental trial and error has been used to find the optimum heating times and temperatures for metal processing. Thermodynamic and kinetic modeling can be used to help determine these time and temperature parameters on a shorter time scale and lead to more efficient conclusions about the solutionization processes. This work focuses on the use of DICTRA models to optimize these parameters through dissolution of secondary phases, predominantly in Aluminum 2024, 5056, 6061, and 7075 alloy powders. These simulations will be experimentally verified using scanning and transmission electron microscopy, energy dispersive x-ray spectroscopy, and differential scanning calorimetry.

Microstructural Evolution Simulation for Property Prediction in Cold Spray Processing

Danielle Cote, Victor Champagne

The cold spray process is a dynamic powder consolidation technique capable of producing materials with high strength and toughness through an extremely versatile processing system.  In this solid state additive manufacturing process, the consolidated material and mechanical properties are directly dependent on the powder properties. To account for this relationship, a through-process model was developed as a predictive tool to follow the microstructural evolution of the cold spray process – from as-received powder to post processing consolidated material. The significance of the feedstock powder properties becomes evident in this work and will be discussed in terms of kinetic, thermodynamic, and solidification predictive simulations and experimental characterization. The final model predicts material and mechanical properties of the consolidated material as a function of feedstock powder and process parameters.