2020 Technical Division Student Poster Contest: MPMD 2020 Technical Division Undergraduate Student Poster Contest
Sponsored by: TMS Extraction and Processing Division, TMS Functional Materials Division, TMS Light Metals Division, TMS Materials Processing and Manufacturing Division, TMS Structural Materials Division
Program Organizers: TMS Administration

Monday 5:30 PM
February 24, 2020
Room: Sails Pavilion
Location: San Diego Convention Ctr


SPU-10: An In-situ X-ray Synchrotron Radiography Approach to Relating Melt-strategy Parameters to Solidification Dynamics in Laser Fusion Processing of Ti-6Al-4V: Logan White1; Rakesh Kamath1; Ryan1; Yuan Li1; Tao Sun2; Sudarsanam Babu3; Hahn Choo1; 1University of Tennessee, Knoxville; 2Argonne National Laboratory; 3Oak Ridge National Laboratory
     Defining a relationship between key processing parameters and resulting microstructure of fusion-based metal additive manufacturing will allow this process to be used to its fullest potential. A laser-AM simulator (developed in-house at beamline 32-ID-B, APS) was used in this study to probe the effects of line and spot melt strategies on the microstructure of Ti-6Al-4V with the controlling variables being: laser power, spot dwell time and laser scan speed. In-situ dynamic x-ray radiography was used to monitor the laser melting event in the AM-simulator and consequently, measure the liquid-solid interface velocity (V). Further, post-mortem microstructural characterization of the solidified melt-pools was used to indirectly estimate the thermal gradient across the liquid-solid interface (G). The G & V will be used to inform existing heat transfer models which, by providing a better understanding of the melt pool dynamics and resultant microstructure, will enable the elucidation of process-structure relationships in additive manufacturing.

SPU-11: Designing Microscale Tests to Validate the Macroscale Plastic Response in Lightweight Aluminum and Magnesium: Skye Supakul1; Tolin Skov-Black1; Keenan O'Neill1; Scout Garrison1; Josiah Dowell1; Job Rodriguez1; 1University of Nevada, Reno
    This study was a part of the undergraduate senior design project in the Materials Science & Engineering department at the University of Nevada, Reno. The senior design students utilized an array of small-scale testing techniques – such as spherical nano-indentation, micro-pillar compression and micro tensile experiments – to characterize the elastic isotropy, plastic anisotropy, and compression-tension symmetry/asymmetry in large (millimeter sized) individual grains of lightweight aluminum and magnesium. The indentation stress-strain response was analyzed as a function of varying indenter radii (5, 10 and 100 um). These results were compared to more uniaxial loading scenarios such as Focused Ion Beam fabricated micro-pillar compression and micro-tensile tests to identify yield strength and strain hardening behavior. Local crystal lattice orientations were measured by electron backscatter diffraction. The results are discussed in terms of advantages and limitations of each technique to capture elastic isotropy, plastic anisotropy, and compression-tension symmetry/asymmetry in aluminum and magnesium.

SPU-12: Embrittlement of Fe-based FINEMET Ribbons: Nickolaus Bruno1; Ronald Noebe2; Jonah Sayre1; Thomas Trautman1; 1South Dakota School of Mines and Technology; 2NASA Glenn Research Center
    FINEMET ribbons are an emerging advanced material with potential uses in high-efficiency electronics systems due to their unique and advantageous magnetic properties. Properties such as magnetic coercivity, anisotropy, and relative permeability can be controlled in these materials by strain annealing processes. However, Fe-based FINEMET-type ribbons are susceptible to severe embrittlement during low temperature annealing. The objective of the present study aims to understand or elucidate the embrittlement mechanism in FINEMET ribbons through characterization of mechanical properties extracted from uniaxial tension tests and thermomechanical analysis (TMA). Moreover, microscopy is performed to characterize inherent defects, such as cracks and pits, created during ribbon melt-spinning synthesis to better understand materials behavior for the design of a strain annealing system.

SPU-13: Impact of Surfactant Concentration and Type on Bilge Water Emulsions During Static and Dynamic Ageing: Rina Sabatello1; 1Purdue University
    Oil-in-water emulsions (O/W) present in the bilge of ocean vessels are inefficiently filtered, causing oil discharge at sea and increasing oil pollution. Separation of oil is difficult due to the presence of surfactants that stabilize oil droplets. This study investigates model bilge water emulsions by examining their drop diameter at different surfactant concentration while ageing in static and dynamic conditions. Droplet diameter decreased with increasing surfactant concentration during static and dynamic ageing. Static ageing with SLES and Triton X-100 showed coalesced drops at concentrations below 10 and 100 ppm, respectively. Dynamic ageing caused droplet coalescence below 100 ppm SLES and 500 ppm Triton X-100. Dynamic ageing led to coalescence more quickly than static ageing. SLES was more effective than Triton X-100 in preventing coalescence at low concentrations. Overall, the stability of dynamically aged O/W emulsions in bilge water were dependent on surfactant type and concentrations up to 500 ppm.

SPU-14: Low Density, High-temperature Syntactic Foam for Additive Manufacturing: Samantha Maness1; Brett Compton1; 1University of Tennessee, Knoxville
    Syntactic foams are a class of composite materials created by binding hollow spherical particles within a matrix and are primarily characterized by their high strength-to-density ratio. Properties of the foams can be tailored through factors such as relative loading of microspheres and the degree of heat treatment during post-processing. These characteristics have motivated widespread use of syntactic foams in lightweight industrial applications. At the same time, additive manufacturing has emerged as an efficient method to create components with custom or complex structures. However, application of syntactic foams as feedstocks for additive manufacturing is limited by the constituent microspheres’ tendency to cause jamming when present in significant amounts. In this work, we characterize a new technique for creating low-density, high temperature syntactic foam structures via material extrusion additive manufacturing comprised of epoxy resin, glass microballoons, and solvent blend that acts as a fugitive carrier for the composite constituents.

SPU-15: Overcoming Oxidation of CMSX-4 to Determine the Thermophysical Properties in the Liquid State: Zane Smith1; 1Purdue University
    Wetting, as measured by the contact angle, plays an important role in filling fine features in superalloy investment casting. The wetting of CMSX-4, a common single crystal casting alloy, has been studied. Previous studies have shown CMSX-4 is highly reactive to oxidization in normal investment casting conditions, 1x10-3 Torr vacuum pressure, which prevents measuring the contact angle. Earlier attempts at obtaining the wetting properties in a gettered argon atmosphere have been unsuccessful. In this study, two different methods: nickel electroplating and a fused silica glass encapsulation system were attempted in hopes to measure the contact angle. Nickel electroplating onto CMSX-4 of various thicknesses resulted in a thin oxide layer less than 1 micron. Therefore, glass encapsulations of the alloy were attempted to ensure no oxygen could react with the alloy. These experiments resulted in less oxidation, however, an oxide layer still formed preventing measurements of the contact angle.