Additive Manufacturing and Innovative Powder Processing of Functional and Magnetic Materials: On-Demand Oral Presentations
Sponsored by: TMS Functional Materials Division, TMS Materials Processing and Manufacturing Division, TMS: Additive Manufacturing Committee, TMS: Magnetic Materials Committee, TMS: Powder Materials Committee
Program Organizers: Emily Rinko, Honeywell Fm&T; Iver Anderson, Iowa State University Ames Laboratory; Markus Chmielus, University of Pittsburgh; Emma White, DECHEMA Forschungsinstitut; Deliang Zhang, Northeastern University; Andrew Kustas, Sandia National Laboratories; Kyle Johnson, Sandia National Laboratories

Monday 8:00 AM
March 14, 2022
Room: Additive Technologies
Location: On-Demand Room


Additive Manufacturing of Electrical Steels: Opportunities to Link Microstructure and Design: Alex Plotkowski1; Chris Fancher1; Michael Haines2; Fred List1; Keith Carver1; Benjamin Stump1; Andrew Kustas3; Peter Wang1; John Coleman1; Amiee Jackson1; Suresh Babu2; Ryan Dehoff1; 1Oak Ridge National Laboratory; 2University of Tennessee Knoxville; 3Sandia National Laboratory
    Significant recent research has successfully demonstrated that additive manufacturing techniques may be used to process electrical steels, including high-Si compositions that are challenging to process via conventional deformation-based processes. These advances have the potential to enable the design and fabrication of novel electromechanical devices that utilize the geometric freedom of AM processing. However, the geometry of a component is intimately linked with the process behavior, thermal conditions, microstructure, and ultimately, the resulting properties and performance of the printed component. This work will provide several examples of the linkages between process, microstructure, and properties for additively manufactured electrical steels. Based on this research, several opportunities for controlling microstructure and properties to produce next-generation electromechanical machines will be explored.

Modeling Alignment of Magnetic Particles in Functionalized Magnetic 3D Printer: Abhishek Sarkar1; M. Paranthaman2; Cajetan Nlebedim1; 1Ames Laboratory; 2Oak Ridge National Laboratory
    Additive manufacturing via 3-D printing has become a frontier in materials research, including its application in the development and recycling of permanent magnets. We present a mathematical framework which predicts the degree of alignment (DoA) in an in-situ aligned 3D printed bonded magnets. A multiphysics model is developed which couples the harmonious interactions of magnetic particles in a viscous polymer under an external magnetic field. Experimental validation of DoA predictions is performed using Nd-Fe-B+Sm-Fe-N in Nylon12 and Sm-Co in PLA. A parametric analysis is performed to study the effect of alignment field strength, magnetic loading fraction, extrusion load, and particle size on DoA. The model predicts a competing behavior between particle-fluid and particle-particle interactions under an applied magnetic field. The model provides a framework to efficiently predict the DoA in tandem with a functionalized-magnetic 3D printer and allows the user to adjust the operating parameters according to the desired DoA.

Influence of Composition and Microstructure on Magnetic Properties of Additively Manufactured Fe/Co/Ni Based Soft Magnetic Alloys: SaiSree Varahabhatla1; Mohansaikiran Nartu1; Sriswaroop Dasari1; Abhishek Sharma1; Varun Chaudhary1; Srinivas Mantri1; Raju Ramanujan1; Rajarshi Banerjee1; 1University of North Texas
    While there has been substantial effort focused on additive manufacturing of structural alloys over the past few decades, there have been rather limited efforts on AM of functional alloys, such as magnetic materials. This study will focus on laser additive processing of magnetic alloys using the laser engineered net shaping (LENS) process that falls under the category of directed energy deposition processes. Soft and semi-hard magnetic binary and ternary alloys of different types comprising Fe, Co& Ni ferromagnetic elements have been processed using LENS. The LENS technique can be effectively used to process compositionally-graded alloys by systematically varying the flow rates from individual powder hoppers that comprise the feedstock. Influence of Fe/Co ratio and B2 ordering on the magnetic properties of as-deposited and heat treated Hiperco type soft magnetic alloys will also be discussed in this presentation. This work shows the feasibility of AM processing of soft magnetic materials.

Mapping the Selective Laser Melting Parameter-thermophysical Property Space of a Ni51.2Ti Alloy Using a Combined Experimental and Computational Approach: Asher Leff1; Nathan Hite2; Chen Zhang2; Adam Wilson1; Raymundo Arroyave2; Alaa Elwany2; Ibrahim Karaman2; Darin Sharar1; 1DEVCOM Army Research Laboratory; 2Texas A&M
    Shape memory alloys like NiTi have been identified as showing promise for thermal energy storage applications. The reversible martensitic transformation these materials undergo can be used to absorb and release heat energy as enthalpy of transformation in order to mitigate the effects of thermal transients. Additive manufacturing (AM) is highly desirable as a processing route for thermal management devices because it enables the production of complex geometries that maximize heat transfer. Further, it has been demonstrated that the transformation temperatures and other thermal properties of NiTi can be tuned by adjusting the AM processing parameters used. In this work, an iterative analytical modeling, design of experiments, and machine learning approach was used to identify the bounds of the selective laser melting parameter space for Ni51.2Ti and to assess the effects of individual print parameters and composite variables such as volumetric energy density on the thermophysical properties of the resultant parts.

Additively Manufactured Nitinol for Prescribed Properties and Prediction of Its Bulk Elastic Properties by Molecular Dynamic Simulation: Jeongwoo Lee1; Yung Shin1; 1Purdue University
    Due to such special mechanical properties, Nitinol has become one of the most promising shape-memory materials for various applications in engineering fields. In this work, Nitinol structures were synthesized in a fully dense form using an additive manufacturing method from elemental powders to arrive at the prescribed final chemical compositions. Combined with proper post-heat treatments prescribed overall chemical and phase compositions were obtained to achieve requisite mechanical and phase transformation properties. The transformation temperatures of Nitinol samples were controlled accurately by less than 5°C away from the target by changing post-heat treatment conditions. The mechanical properties were controlled to achieve various elastic modulus based on phase compositions. In addition, molecular dynamics simulation based on the polycrystalline microstructure was successfully carried out to predict realistic bulk elastic properties, which can be used to show the effects of different grain structures and phase distribution in Nitinol.

Process-structure-property Relationships in Laser Powder Bed Fusion of Permanent Magnetic Nd-Fe-B: Julan Wu1; Nesma Aboulkhair2; Michele Degano1; Richard Hague1; Ian Ashcroft1; 1University of Nottingham; 2University of Nottingham (UK) and Technology Innovation Institute (UAE)
    We present a parametric study on the laser powder bed fusion (L-PBF) of Nd-Fe-B magnet. The microstructure and the magnetism of the L-PBF Nd-Fe-B were also studied. Consequently, the issues encountered with utilising L-PBF for the production of relatively high-density Nd-Fe-B magnetics are elucidated and discussed. Furthermore, new insights on the geometrical constraints on the shape complexity and design freedom during L-PBF of this material are presented. High-density samples with remanence of 0.65T and maximum energy product of 62 kJ/m3 were successfully produced, whilst demonstrating the integrity of the parts was affected by the scan speed and hatch distance; in addition, the sample’s size and geometry were also found to influence the success of building within the LPBF system. The relative density and integrity of the produced samples were mainly constrained by the intrinsic brittle mechanical property of intermetallic Nd2Fe14B phase and the liquation cracking induced during laser processing.