Development of Light Weight Alloys and Composites : Microstructure and Properties: Composites I
Program Organizers: Ramasis Goswami, Naval Research Laboratory; Nikhil Gupta, New York University; Tanjore Jayaraman, United States Air Force Academy; Aashish Rohatgi, Pacific Northwest National Laboratory
Monday 8:00 AM
October 18, 2021
Room: A214
Location: Greater Columbus Convention Center
Session Chair: Aashish Rohatgi, PNNL; Ramasis Goswami, NRL
8:00 AM Invited
Development of a High-temperature High Strength Aluminum Alloys by Microstructure Tuning: Kamanio Chattopadhyay1; Ujjval Bansal1; Mahander Singh1; Shyam Sinha1; Sukla Mondol2; Surendra Makineni1; 1Indian Institute of Science; 2NIT Warangal
One of the current challenges in light alloys is to develop aluminum alloys that can withstand up to 250 °C. The present talk summarizes our recent experiments on Al-Cu alloys with micro-addition of Si, Zr, Ta, Nb, or Hf promoting high-temperature stable ordered L12 precipitates that heterogeneously nucleate copper-rich θ”/θ’ plates and also partitions into them. Si or Nb suppresses the discontinuous precipitation of L12 precipitates and accelerates their kinetics. The resultant microstructure shows higher coarsening resistance and stability at high temperatures. Some of the alloys show 0.2% yield strength > 250 MPa at 250 °C. Atomic-scale compositional and structural analysis by atom probe tomography (APT) and aberration-corrected transmission electron microscopy (TEM) were used to reveal the mechanisms related to high-temperature behavior of these alloys.
8:40 AM Invited
A Data-driven Analysis for Selection of Ti-based Alloys for Aircraft Landing Gear Beams and Future Directions: Tanjore Jayaraman1; Canumalla Ramachandra2; 1University of Michigan-Dearborn; 2Weldaloy Specialty Forgings
Titanium alloys find diverse aerospace applications. Data are available in the open literature on many Ti alloys for landing gears that require high strength, high toughness, fatigue resistance, and corrosion resistance. We analyzed the available relevant data on these titanium alloys. Advanced statistical analysis, namely, cluster analysis (CA), principal component analysis (PCA), and multiple-attribute decision making (MADM), were applied to hear the voice of the data. PCA and CA not only consolidated the MADM ranks of the alloys but also grouped similar alloys. The rank assigned by several MADMs, including SAW (selective additive weighting), MEW (multiplicative exponent weighing), and OCRA (operative competitiveness ratio) were consistent. The investigation highlights similarities (and differences) across several grades/variants of the alloys, suggests potential replacement or substitute for the existing alloys, and also provides possible directions for improvement and/or development of these alloys to ensure robustness and reliability.
9:20 AM
Existing and Emerging Applications of Machine Learning in Design, Synthesis, and Characterization of Metal Matrix Composites: Amir Kordijazi1; Pradeep Rohatgi1; 1University of Wisconsin-Milwaukee
We present an overview of existing and emerging machine learning (ML) applications in the design, synthesis, and characterization of metal matrix composites (MMC). We have shown that machine learning approaches can be used in three different categories: property prediction, microstructure analysis, and process optimization, which are correlated with three different types of machine learning techniques: regression, classification, and optimal control, respectively. Mechanical, tribological, corrosion, and wetting properties of various MMCs have all been successfully predicted using machine learning algorithms. However, despite their enormous capabilities, ML methods such as computer vision, which is useful for microstructural characterization and defect detection, and optimization algorithms (e.g., reinforcement learning) have not been widely utilized for the design, processing, and characterization of metal matrix composites. We conclude that ML offers enormous opportunities to gain more knowledge about MMC’s; they can help design, manufacture, and deploy new MMC’s significantly faster at a fraction of the cost.
9:40 AM
Energy Efficient Solid-state Alloying and Composite Manufacturing: Kumar Kandasamy1; 1Enabled Engineering
Alloys and composite materials are mostly made using ladle metallurgy where the different alloying elements and reinforcement phase are added into the liquid melt in the form of pure elements and phases, or as master alloys. On the other hand, solid-state processing is done via ball milling and severe plastic deformation processes. The current methods are energy intensive processes, or time consuming and has scalability issues due to inherent process difficulties. The SolidStir is a novel solid-state technology that enables continuous severe plastic deformation, microstructure modification, solid-state alloying, composite material manufacturing and solid-state recycling. The technology is highly suitable for in-situ alloying and composite manufacturing using reactive material combinations and manufacturing composite materials using immiscible systems. In this presentation, the process principles, the mechanism of SolidStir alloying, and the benefits of technology will be discussed with practical examples.
10:00 AM Break
10:20 AM Invited
Non-Rule-of-Mixtures Thermal Diffusivity in Core-Shell-based Nanocrystalline Composite Ceramics: James Wollmershauser1; Kevin Anderson2; Benjamin Greenberg2; Heonjune Ryou1; Edward Gorzkowski1; Boris Feigelson1; 1U.S. Naval Research Laboratory; 2National Research Council Postdoctoral Research Fellow sited at U.S. Naval Research Laboratory
Nanocrystalline ceramics demonstrate property improvements over larger-grain-sized ceramics such as increased hardness, strength, and, potentially, damage tolerance. These property improvements result from “confinement” effects of modes of strain accommodation and crack propagation. Combining two or three different ceramic materials into a nanocrystalline composite ceramic provides the opportunity to design other properties that are generally expected to follow a rule-of-mixtures law, such as thermal conductivity, while capitalizing on mechanical property improvements inherent to nanocrystalline materials. Recent work at NRL has combined particle atomic layer deposition (pALD) with Environmentally Controlled – Pressure Assisted Sintering (EC-PAS) to synthesize dense nanocomposite ceramics from core-shell nanopowders. Limited experiments suggest that thermal diffusivity (proportional to thermal conductivity) of these nanocomposites do not follow a simple rule-of-mixtures law. Instead, the thermal properties of the nanocrystalline constituent with a lower thermal diffusivity controls the thermal diffusivity of the nanocomposite ceramic.