Engineering Ceramics: Microstructure-Property-Performance Relations and Applications: On-Demand Poster Presentations
Sponsored by: ACerS Engineering Ceramics Division
Program Organizers: Young-Wook Kim, University of Seoul; Hua-Tay Lin, Guangdong University of Technology; Junichi Tatami, Yokohama National University
Friday 8:00 AM
October 22, 2021
Room: On-Demand Poster Hall
Location: MS&T On Demand
Discrete Element Modeling of Machining Process for Thermal Barrier Coating: Jian Zhang1; Dan Koo1; Hye-Yeong Park2; Yeon-Gil Jung2; Jing Zhang1; 1Indiana University – Purdue University Indianapolis; 2Changwon National University
In this work, the machining process for the thermal barrier coating is simulated using the discrete element model (DEM) method. The model is first calibrated using a typical ceramic material for mechanical property characterization. Then the model is applied to thermal barrier coating. The crack evolution and the associated stress were analyzed. The results were compared with continuum mechanics for brittle materials.
Engineering Mineral Porosity as a Method for Studying Weathering Rates In Water-rock Systems: William Taylor1; Brian Gorman1; Alexis Navarre-Sitchler1; 1Colorado School of Mines
Natural groundwater system porosity occurs in many topologies and replication of these physical heterogeneities is important for lab-scale investigations of water-rock interactions such as dissolution and weathering. To address this need, this study investigates the use of ceramic processing techniques to engineer well defined pore patterns into the mineral anorthite (CaAl2Si2O8, CAS) for use in dissolution experiments. To do so, powders of CaCO3, Al2O3, and SiO2 are calcined in several steps at 1200°C, just below the eutectic for the CAS system. As seen in previous studies, particle size plays a large role in the final phase and reaction times, and milling procedures to achieve particle sizes <~10 um needed to be optimized prior to calcination. Before final sintering and densification, a sacrificial template composed of carbon black or polymethylmethacrylate (PMMA) is arranged in the desired geometry in order to vary the porosity characteristics including size, interconnectivity, shape, and topology.
Low Temperature Pressureless Sintering of Silicon Carbide Ceramics with Aluminum Nitride-Yttria-Ceria-Magnesia: Eun Seo Kang1; Young-Wook Kim1; 1The University of Seoul
For cost-effective production of dense silicon carbide (SiC) ceramic parts, pressureless sintering of SiC ceramics at lower temperatures is preferred. This study suggests a new additive composition based on AlN–Y2O3–CeO2–MgO that leads to successful densification of SiC without applied pressure at a temperature as low as 1850°C. The effect of sintering temperature on the mechanical and thermal properties of SiC ceramics sintered with the new quaternary additive was investigated. Fracture toughness of the SiC ceramics continuously increased with increasing sintering temperature because of the growth of platelet SiC grains at temperatures ≥ 1800°C. In contrast, the flexural strength and hardness showed maxima at 1900°C due to the decreased density and increased grain size at higher sintering temperatures. Typical sintered density, fracture toughness, hardness, and flexural strength of the 1850°C-sintered SiC ceramics were 99.1%, 4.7 MPa·m1/2, 23.5 GPa, and 328 MPa at room temperature, respectively.