Advances in Dielectric Materials and Electronic Devices: On-Demand Poster Session
Sponsored by: ACerS Electronics Division
Program Organizers: Amar Bhalla, University of Texas; Ruyan Guo, University of Texas at San Antonio; Rick Ubic, Boise State University; Matjaž Spreitzer, Jožef Stefan Institute
Friday 8:00 AM
October 22, 2021
Room: On-Demand Poster Hall
Location: MS&T On Demand
Dielectric NDE for On-line Cure Monitoring and Defect Detection in Engineered Composites: William Flynn1; Bryan Gamboa1; Sean Garnsey1; Ruyan Guo1; Amar Bhalla1; 1University of Texas at San Antonio
Large-scale, continuous manufacturing processes require systems that provide immediate feedback on process yield, and defect detection for quality control. Several non-destructive evaluation (NDE) technologies are available to meet this need, each with its own advantages and drawbacks. Dielectric NDE using capacitive sensors is one candidate for in-situ cure monitoring and on-line defect detection in multi-phase composites. Inkjet printing of the functional materials is an emerging potential fabrication technique that enables flexible devices at relatively low cost. In this paper, we report the results on the evaluation of co-planar interdigital electrode sensors fabricated via inkjet printing for cure monitoring and defect detection. Finite-elements modeling (COMSOL) is used to explore suitable sensor design. Simulation results are used to instruct fabrication of prototype capacitive sensors. Ink-jet printed sensor performance is evaluated and compared to simulation to understand the feasibility of this NDE approach.Authors acknowledge the collaboration with Boral IPH in these efforts.
Poster
Features on the Structural Phase Transition in La-modified AgNbO3 Lead-free Ceramics: Karine Felix Santos de Jesús1; Atair Carvalho da Silva1; Yanela Mendez-González2; Ruyan Guo3; Amar Bhalla3; Jose de los Santos Guerra1; 1Universidade Federal de Uberlandia; 2Universidad de La Habana; 3The University of Texas at San Antonio
Silver niobate (AgNbO3 – AN) based compounds have attracted special attention over the last decade due to their very interesting physical properties, which make them promising materials for practical applications due to the high recoverable energy density and exceptional electromechanical response. Therefore, they have been considered as excellent lead-free alternatives for energy storage and high piezoelectric performance devices. The aim of the present work is to investigate the structural phase transition characteristics of rare-earth modified AN electroceramics. In particular, the influence of the lanthanum content (Ag1–3xLaxNbO3) on the structural properties, investigated from Raman spectroscopy, and the dielectric response have been analyzed, both in a wide temperature range. The observed anomalous behaviors have been analyzed and discussed within the framework of the current phenomenological models found in the literature. The authors thank CNPq (303447/2019-2), FAPEMIG (PPM-00661-16 and APQ-02875-18) and CAPES (Finance Code 001) Brazilian agencies for the financial support.
Poster
Graphs Theory and Electrophysical Parameters Characterization: Vojislav Mitic1; Aleksandar Stajcic2; Branislav Randjelovic1; Srdjan Ribar3; Bojana Markovic3; Maria Cebela4; Ivana Radovic5; Hans Fecht6; 1University Nis; 2University of Belgrade, Center of Microelectronic Technologies, Institute of Chemistry, Technology and Metallurgy – National Institute of the Republic of Serbia, Belgrade; 3University of Belgrade; 4University of Belgrade, ‘VINČA’ Institute of Nuclear Sciences – National Institute of the Republic of Serbia, Belgrade; 5University of Belgrade,‘VINČA’ Institute of Nuclear Sciences – National Institute of the Republic of Serbia, Belgrade; 6University Ulm, Institute of Functional Nanosystems FNS
Nanoparticles of BaTiO3 were modified with yttrium salt, in order to enhance its electronic properties. Graph theory was applied for calculation of capacitance change at the interface between grains under the influence of the applied voltage and electroconductivity at nanocrystal diamonds. Measurements were performed on bulk samples, showing that modified nano- BaTiO3 can retain stability up to 100V. Grains were presented as edges in graph between vertices and capacitance change was successfully calculated on grain boundaries, based on different number of neighboring grain and applied DC bias. Calculations presented as 1D, 2D and 3D cases were performed, proving that graph theory could be applied to characterize intergranular relations based on bulk measurements. Based on our findings, it is obvious that this approach could solve measurement problems, which cannot be performed on nano level, opening new perspective in miniaturization of electronic materials.
Poster
Study and Physical Characterization of Hybrid PVDF/Ceramic Composites: Evaristo Alexandre Falcăo1; Atair Carvalho da Silva2; Yanela Mendez-González3; Ruyan Guo4; Amar Bhalla4; Jose de los Santos Guerra2; 1Universidade Federal da Grande Dourados; 2Universidade Federal de Uberlandia; 3Universidad de La Habana; 4The University of Texas at San Antonio
Poly(vinylidene fluoride) (PVDF) compounds present very wide application in strategic technological areas due to the intrinsic ferroelectric property, which allows their use in electro-electronic devices, such as electro-mechanical and electro-thermal transducers, speakers, sensors, and to stimulate the bone tissue growth in animals. Although PVDF presents the best electroactive properties, compared to other ferroelectric polymers, these properties are lower than those observed in ferroelectric ceramics. In this work, hybrid composites based on PVDF/BaTiO3, PVDF/BaFe12O19, and PVDF/SrFe12O19 were studied considering different doping concentrations. The physical properties have been investigated from structural, microscturcutral, optical and dielectric characterizations. The XRD, FT-IR, and AFM measurements confirmed the incorporation of dopants in the polymeric matrix. An increase in the dielectric permittivity caused by the ceramic doping was also observed. The authors thank Fundect, CNPq (483683/2010-8, 208232/2014-1 and 303447/2019-2), FAPEMIG (PPM-00661-16 and APQ-02875-18), FINEP (04.13.0448.00/2013) and CAPES (Finance Code 001) Brazilian agencies for the financial support.
Poster
Sensitivity Analysis on the Application of Direct Piezo-electric Effect Using the Finite-element Extended Complex Variable Method: Carlos Acosta1; Jose de los Santos Guerra2; Ruyan Guo3; Amar Bhalla3; 1Inghieri Solutions LLC; 2Universidade Federal de Uberlandia; 3University of Texas at San Antonio
The main goal of this investigation is to focus on the application and optimization of the direct piezoelectric effect in energy harvesting from low-frequency mechanical vibration. To achieve this goal, a sensitivity analysis was performed to study the coefficients that characterize the material properties through the implementation of the finite-element extended complex variable method. This numerical approach allows the computation of derivatives with respect to changes in geometry, material properties, and boundary loads by an iterative approach.This method offers significant advantages compared to the traditional finite-element approach given the highly accurate derivative information that can be obtained. The extended complex variable method was implemented in Python and the system of complex equations was solved using Scipy. The results showed good agreement with voltages and mechanical displacements form values obtained using commercial finite-element software.