Late News Poster Session: Advanced Materials
Program Organizers: TMS Administration
Monday 5:30 PM
February 28, 2022
Room: Exhibit Hall C
Location: Anaheim Convention Center
A-23: Computational Discovery of Ultra-high Strength BCC Refractory Metal-based MPEAs: Kate Elder1; Joel Berry1; Aurelien Perron1; Hunter Henderson1; Jibril Shittu1; Zachary Sims1; Scott McCall1; Joseph McKeown1; 1Lawrence Livermore National Laboratory
Body centered cubic (BCC) refractory metal-based multi-principal element alloys (MPEAs) are known for maintaining a high yield stress at elevated temperatures, an excellent mechanical property, necessary for operation in extreme environments. To exploit the enhanced mechanical properties, tailored MPEAs with both high strength and robust BCC phase stability are needed. However, these properties vary drastically with temperature, number of elements, and composition of elements. Through analytical calculations, we investigate all MPEAs from the Al-Cr-Fe-Hf-Mo-Nb-Ta-Ti-V-W-Zr family with up to eleven elements to identify candidate alloys that maintain a high yield stress or specific yield stress. These results are filtered with phase stability predictions from CALPHAD to ensure that the BCC phase is stable at high temperatures. Select compositions predicted to maintain high strength or specific strength and a stable BCC phase are manufactured and mechanically tested to validate the tailored MPEA design process. Prepared by LLNL under Contract DE-AC52-07NA27344.
A-24: Geometric Analysis of the Growth Front of Iron Borides Fe2B in AISI-1018 Steel: Katia Andrade Michel; 1
I will establish a model to explain the formation of the growth front of the Fe2B phase of iron borides in AISI-1018 steel. I am studying the effect of the temperature and treatment time of the boruration process with paste for the formation of iron borides in a low carbon steel (AISI-1018) considering the measurements of depth, area, the geometry of the phase formed from iron borides and the fractal geometry. The growth front is considered to have a fractal behavior, which I studied by means of a mathematical analysis that allows estimating the Hurst Exponent and the fractal dimension of the iron boride growth front.
A-25: High Solid Content Porous Cordierite with Controllable Structure Prepared by Pickering Emulsion Technology: Xuezhu Luan1; 1Shenyang University
PCCs with stable three-dimensional microstructures were prepared by Pickering emulsion technique. The prepared precursor of PCCs had the lowest initial Zeta potential to ensure the stable suspension, which was superior compared with previous experiments. The formation of the spherical structure was due to the broken of oil bubbles, and the formation of gradient pore structure was believed to the formation of cordierite and the concomitant consumption of sucrose during the sintering process. PCCs with high solid content of 45 vol. % can be obtained, which had the high porosity, and optimized thermal conductivity. The theory of “oil droplet” three-dimensional accumulation was used to realize the stable and orderly spatial arrangement of micro-emulsion system to obtain structure-controlled PCCs through controlling the precursor.
NOW ON-DEMAND ONLY - A-26: Microstructural Analysis of the Casting Defects in the Low Pressure Turbine Blades: Rafal Cygan1; Łukasz Rakoczy2; Mirosław Antosz1; Dorota Wyrobek2; Tomasz Szczęch2; 1Consolidated Precision Products Poland; 2AGH University of Science and Technology
The production of high-quality turbine blades from Ni-based superalloys poses a challenging problem for the aerospace industry. The occurrence of defects in the final component has become more common with the increasing complexity of the blades. In parallel, superalloy development has improved the service capabilities of these parts, but these new generation superalloys have encountered more casting difficulties. This work presents selected results of the analysis of casting defects detected in a low-pressure turbine blade. To identify the source of their occurrence, non-destructive tests, light microscopy, scanning electron microscopy, and X-ray dispersion spectroscopy experiments were carried out. On the basis of the conducted research, it was found that the main reason for the occurrence of casting defects was the local segregation of Al and Ti and the oxidation of the superalloy during the casting. This is indicated by the complex morphology of numerous precipitates and their high enrichment in oxygen.
A-27: Self-healing Behavior of Fe-Ni Base Superalloy Based on Spontaneous Segregation of Boron: Chamil Kim1; WooChul Kim1; YongJoo Kim1; WonTae Kim2; Do Hyang Kim1; 1Yonsei University; 2Cheongju University
The superalloy is a material having creep resistance at high temperature, which is an important property. Recently, many studies have been conducted on self-healing as a solution to the high temperature creep resistance. Therefore, this study was conducted to improve the high temperature creep properties of Fe-Ni based superalloy from its self-healing effect of spontaneous boron segregation. δ-Ni3Nb was precipitated in grain boundary under pre-formed crack tip through annealing and it induced the segregation of boron. Boron was confirmed quantitatively through ATP. Due to this self-healing effect and dislocation recovery, a pre-strained and annealed specimen exhibited the longer total elongation, compared to the specimen without an additional element. Finally, creep test can be expected to show that the creep property of specimen with boron is higher than specimen without boron due to self-healing effect and segregation of boron which improves strength of grain boundary.
A-28: Software Design for ICME, PSPP and Multiscale: Deepankar Pal1; Grama Bhashyam1; 1ANSYS
The world of materials science technologies and mechanics of materials have continuously evolved in the past 50 years and more specifically in the last decade to realize a wide range of useful process technologies such as Additive Manufacturing, Controlled casting technologies and Smartphone design and failure analysis. Many academic institutions and industrial solution companies have proposed novel ways to tackle the issues at the interface of mechanics and materials using an Integrated Computational Materials Engineering (ICME) approach with horizonal Process-Structure-Property-Performance (PSPP) and vertical Multiscale, although a building block which can be stacked in vertical, horizontal, hierarchical and cyclic workflow flawlessly with almost inifinte scalability is missing from the solution design. At Ansys, novel fundamental building blocks for solving the above mentioned problems are being designed and will be presented with introductory conceptual examples on Crystal Plasticity for further discussion and feedback from the Materials community at large.