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Materials Science and Engineering
Mechanical and Aerospace Engineering Faculty Research & Creative Works
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Articles 61 - 85 of 85
Full-Text Articles in Engineering
Modeling And Simulation Of A Laser Deposition Process, Frank W. Liou, Zhiqiang Fan, Heng Pan, Kevin P. Slattery, Mary Kinsella, Joseph William Newkirk, Hsin-Nan Chou
Modeling And Simulation Of A Laser Deposition Process, Frank W. Liou, Zhiqiang Fan, Heng Pan, Kevin P. Slattery, Mary Kinsella, Joseph William Newkirk, Hsin-Nan Chou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A laser deposition process involves the supply of metallic powders into a laser-heated spot where the powder is melted and forms a melt puddle which quickly solidifies into a bead. In order to design an effective system, the laser beam, the powder beam, and their interactions need to be fully understood. In this paper, the laser-material interaction within the melt pool is reported using a multi-scale model: A macroscopic model to model mass, heat, and momentum transfer. Experiments were also conducted to validate the simulation model.
Aqueous-Based Extrusion Fabrication Of Ceramics On Demand, Michael S. Mason, Tieshu Huang, Robert G. Landers, Ming-Chuan Leu, Greg Hilmas, Michael W. Hayes
Aqueous-Based Extrusion Fabrication Of Ceramics On Demand, Michael S. Mason, Tieshu Huang, Robert G. Landers, Ming-Chuan Leu, Greg Hilmas, Michael W. Hayes
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Aqueous-Based Extrusion Fabrication is an additive manufacturing technique that extrudes ceramic slurries of high solids loading layer by layer for part fabrication. The material reservoir in a previously developed system has been modified to allow for starting and stopping of extrusion process on demand. Design pros and cons are examined and a comparison between two material reservoir designs is made. Tests were conducted to determine the optimal deposition parameters for starting and stopping of the extrudate on demand. The collected test data is used to create a process model that describes the relationship between ram velocity and material extrusion rate. …
Numerical Simulation Of The Evolution Of Solidification Microstructure In Laser Deposition, Zhiqiang Fan, Todd E. Sparks, Frank W. Liou, Anand Jambunathan, Yaxin Bao, Jianzhong Ruan, Joseph William Newkirk
Numerical Simulation Of The Evolution Of Solidification Microstructure In Laser Deposition, Zhiqiang Fan, Todd E. Sparks, Frank W. Liou, Anand Jambunathan, Yaxin Bao, Jianzhong Ruan, Joseph William Newkirk
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A predictive model is developed to simulate the evolution of the solidification microstructure during the laser deposition process. The microstructure model is coupled with a comprehensive macroscopic thermodynamic model. This model simulates dendritic grain structures and morphological evolution in solidification. Based on the cellular automata approach, this microstructure model takes into account the heterogeneous nucleation both within the melt pool and at the substrate/melt interface, the growth kinetics, and preferential growth directions of dendrites. Both diffusion and convection effects are included. This model enables prediction and visualization of grain structures during and after the deposition process. This model is applied …
Dielectric Response Of Sr Doped Cacu₃Ti₄O₁₂ Ceramics, Wei Li, Robert W. Schwartz, Aiping Chen, Jinsong Zhu
Dielectric Response Of Sr Doped Cacu₃Ti₄O₁₂ Ceramics, Wei Li, Robert W. Schwartz, Aiping Chen, Jinsong Zhu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Ca1−xSrxCu3Ti4O12 (x=0, 0.1, and 0.2) ceramics were fabricated and their dielectric properties were investigated. It was found that the dielectric constant significantly decreased with the increase of Sr content at low temperature region (<250 K) and remained almost unchanged at high temperature region (>250 K). Three sets of relaxation peaks were observed in electric modulus plots, which were considered to be associated with grains, domain boundaries, and grain boundaries, respectively. Through the analysis of the heights and calculated activation energies of the relaxation peaks, it is strongly believed that the suppressed dielectric constant is related to the change of domain boundaries with Sr doping. ©2007 American Institute of Physics
Fracture Toughness Of Ceramic Moulds For Investment Casting With Ice Patterns, Qingbin Liu, Ming-Chuan Leu, Von Richards
Fracture Toughness Of Ceramic Moulds For Investment Casting With Ice Patterns, Qingbin Liu, Ming-Chuan Leu, Von Richards
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Ice patterns can be used to make ceramic investment moulds for metal castings. Owing to the characteristics of ice, the ceramic mould must be made at subzero temperatures and consequently, requires a different formulation than shells built at room temperature. Success of this process depends greatly on the fracture toughness of mould materials. The present paper describes the experimental results of fracture toughness of mould materials processed from different compositions. The Taguchi method was used to reduce the trial runs. The parameters considered included the ratio of fibre containing fused silica and aluminosilicate powders, the volume of binder and the …
Freeform Extrusion Of High Solids Loading Ceramic Slurries, Part I: Extrusion Process Modeling, Michael S. Mason, Tieshu Huang, Robert G. Landers, Ming-Chuan Leu, Greg Hilmas
Freeform Extrusion Of High Solids Loading Ceramic Slurries, Part I: Extrusion Process Modeling, Michael S. Mason, Tieshu Huang, Robert G. Landers, Ming-Chuan Leu, Greg Hilmas
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A novel, solid freeform fabrication method has been developed for the manufacture of ceramic-based components in an environmentally friendly fashion. The method is based on the extrusion of ceramic slurries using water as the binding media. Aluminum oxide (Al2O3) is currently being used as the part material and solids loading as high as 60 vol. % has been achieved. This paper describes a novel manufacturing machine that has been developed for the extrusion of high solids loading ceramic slurries. A critical component of the machine is the deposition system, which consists of a syringe, a plunger, …
Freeform Extrusion Of High Solids Loading Ceramic Slurries, Part Ii: Extrusion Process Control, Michael S. Mason, Tieshu Huang, Robert G. Landers, Ming-Chuan Leu, Greg Hilmas
Freeform Extrusion Of High Solids Loading Ceramic Slurries, Part Ii: Extrusion Process Control, Michael S. Mason, Tieshu Huang, Robert G. Landers, Ming-Chuan Leu, Greg Hilmas
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Part I of this paper provided a detailed description of a novel fabrication machine for high solids loading ceramic slurry extrusion processes and presented an empirical model of the ceramic extrusion process, viewing ram velocity as the input and extrusion force as the output. A constant extrusion force is desirable as it correlates with a constant material deposition rate and, thus, good part quality. The experimental results used to construct the model demonstrated that a constant ram velocity will not necessarily produce a constant extrusion force. In some instances the extrusion force increased until ram motor skipping occurred, and process …
Applications Of A Hybrid Manufacturing Process For Fabrication And Repair Of Metallic Structures, Frank W. Liou, Kevin P. Slattery, Mary Kinsella, Joseph William Newkirk, Hsin-Nan Chou, Robert G. Landers
Applications Of A Hybrid Manufacturing Process For Fabrication And Repair Of Metallic Structures, Frank W. Liou, Kevin P. Slattery, Mary Kinsella, Joseph William Newkirk, Hsin-Nan Chou, Robert G. Landers
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Since its appearance, rapid prototyping technology has been of interest to various industries that are looking for a process to produce/build a part directly from a CAD model in a short time. Among them, the direct metal deposition process is the only process which directly manufactures a fully dense metal part without intermediate steps. However, challenges of the direct metal deposition process include building overhang structures, producing precision surfaces, and making parts with complex structures. Coupled between the additive and the subtractive processes into a single workstation, the integrated process, or hybrid process, can produce a metal part with machining …
Evaluation Of Mechanical Properties And Microstructure For Laser Deposition Process And Welding Process, Yaxin Bao, Jianzhong Ruan, Todd E. Sparks, Jambunathan Anand, Joseph William Newkirk, Frank W. Liou
Evaluation Of Mechanical Properties And Microstructure For Laser Deposition Process And Welding Process, Yaxin Bao, Jianzhong Ruan, Todd E. Sparks, Jambunathan Anand, Joseph William Newkirk, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Laser Aided Manufacturing Process (LAMP) can be applied to repair steel die/molds which are currently repaired using traditional welding process in industry. In order to fully understand the advantages of laser deposition repair process over traditional welded-repair process, the mechanical properties such as tensile strength and hardness of H13 tool steel samples produced by these two processes were investigated. The microstructure and fracture surface of the samples were analyzed using optical microscope and SEM (Scanning Electron Microscope). Moreover, depositions on substrates with different shapes were studied to evaluate the performance of LAMP on damaged parts with complicated geometric shape.
Comparison Of Thermal Properties Of Laser Deposition And Traditional Welding Process Via Thermal Diffusivity Measurement, Yu Yang, Omoghene Osaze Obahor, Yaxin Bao, Todd E. Sparks, Jianzhong Ruan, Jacquelyn K. Stroble, Robert G. Landers, Joseph William Newkirk, Frank W. Liou
Comparison Of Thermal Properties Of Laser Deposition And Traditional Welding Process Via Thermal Diffusivity Measurement, Yu Yang, Omoghene Osaze Obahor, Yaxin Bao, Todd E. Sparks, Jianzhong Ruan, Jacquelyn K. Stroble, Robert G. Landers, Joseph William Newkirk, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Laser deposition is an effective process for mold and die repair. In order to improve the part repair quality, the process impact on thermal diffusivity and thermal conductivity needs to be understood for laser deposited, welded and virgin H13. In this paper, H13 tool steel samples were made by laser deposition, welding and virgin H13 and then cut into pieces. Experiments were conducted to investigate the thermal diffusivity and conductivity. A laser flash method is used to test these samples. The future work and opportunities are also summarized.
Maxwell-Wagner Relaxations And Their Contributions To The High Permittivity Of Calcium Copper Titanate Ceramics, Wei Li, Robert W. Schwartz
Maxwell-Wagner Relaxations And Their Contributions To The High Permittivity Of Calcium Copper Titanate Ceramics, Wei Li, Robert W. Schwartz
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Calcium copper titanate ceramics were fabricated by cold isostatic pressing at various calcination and sintering conditions. Depending on fabrication condition, three electrical responses were observed in the combined modulus and impedance plots, indicating the presence of two Maxwell-Wagner relaxations. These electrical responses show different response to temperature and applied field. The activation energies, as well as the driving force factors, were calculated for these relations. The determined activation energy values are in the range of 0.57 to 0.65 eV. The contribution of Maxwell-Wagner relaxations to the high permittivity of CCTO and related materials is briefly discussed.
Study Of Ceramic Slurries For Investment Casting With Ice Patterns, Qingbin Liu, Ming-Chuan Leu, Harish Jose, Von Richards
Study Of Ceramic Slurries For Investment Casting With Ice Patterns, Qingbin Liu, Ming-Chuan Leu, Harish Jose, Von Richards
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Ice patterns generated by rapid freeze prototyping or a molding process can be used to make ceramic investment molds for metal castings. Due to the use of ice, the ceramic slurries must be poured around the pattern and cured at sub-freezing temperatures. Success of this process depends greatly on the mold strength after the gelation of the slurries. This paper describes the experimental results of the mold strength after the gelation of the slurries under different compositions. The parameters considered include mixing time, alumino-silicate vs. fused silica ratio, volume of binder, and volume of catalyst. The strength of the gelled …
Characterization And Modeling Of Local Electromechanical Response In Stress-Biased Piezoelectric Actuators, N. Navapan-Traiphol, Robert W. Schwartz, Daniel S. Stutts, J. Wood
Characterization And Modeling Of Local Electromechanical Response In Stress-Biased Piezoelectric Actuators, N. Navapan-Traiphol, Robert W. Schwartz, Daniel S. Stutts, J. Wood
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Numerous investigators have explored the factors that contribute to the high electromechanical performance of stress-biased actuators with particular attention being given to the importance of the extrinsic (domain wall translation) response mechanism. Based on the variation in lateral stress through the thickness of the piezoelectric layer within these devices, it has been suggested that the piezoelectric coefficient varies as a function of position within the layer, though no direct evidence has been previously presented. In this study, the results of Moire interferometry investigations of local strains within these devices are reviewed. The technique permits effective depth-profiling of local deformations at …
Thermal Properties Of La₀.₅Sr₀.₅Co₁₋ₓnixo₃-D Ceramics Using Photopyroelectric Technique, M. T. Sebastian, C. Preethy Menon, J. Philip, Robert W. Schwartz
Thermal Properties Of La₀.₅Sr₀.₅Co₁₋ₓnixo₃-D Ceramics Using Photopyroelectric Technique, M. T. Sebastian, C. Preethy Menon, J. Philip, Robert W. Schwartz
Mechanical and Aerospace Engineering Faculty Research & Creative Works
La0.5Sr0.5Co1-xNixO3-delta (0<= x<= 0.6) ceramics were prepared using a conventional solid-state ceramic route. The thermal properties—thermal conductivity and heat capacity—of these ceramics were measured by the photopyroelectric technique. The thermal conductivity was found to increase with increasing Ni content. These materials were also found to exhibit a metallic-type variation of thermal conductivity with temperature, and no metal-insulator (M-I) transition was found to occur in any of the samples prepared by this route. However, a M-I transition was found to occur in La0.5Sr0.5CoO3-delta samples prepared by hot pressing. The difference is attributed to variations in oxygen content in the samples.
Growth And Optical Properties Of Srbi₂Nb₂O₉ Ferroelectric Thin Films Using Pulsed Laser Deposition, Pingxiong Yang, David L. Carroll, John Ballato, Robert W. Schwartz
Growth And Optical Properties Of Srbi₂Nb₂O₉ Ferroelectric Thin Films Using Pulsed Laser Deposition, Pingxiong Yang, David L. Carroll, John Ballato, Robert W. Schwartz
Mechanical and Aerospace Engineering Faculty Research & Creative Works
High quality SrBi2Nb2O9 ferroelectric thin films were fabricated on platinized silicon using pulsed laser deposition assisted with dc glow discharge plasma. Microstructure and ferroelectric properties of the films were characterized. Optical properties of the thin films were studied by spectroscopic ellipsometry and photoluminescence from the ultraviolet to the infrared region. Optical constants, n~0.56 in the infrared region and n~2.24 in the visible spectral region, were determined through multilayer analyses on their respective pseudodielectric functions. The band-gap energy is estimated to be 3.60 eV. A photoluminescence peak at 0.78 µm, whose intensity decreases with decreasing temperature, was observed when excited with …
Electrical Properties Of Srbi₂Ta₂O₉ Ferroelectric Thin Films At Low Temperature, Pingxiong Yang, David L. Carroll, John Ballato, Robert W. Schwartz
Electrical Properties Of Srbi₂Ta₂O₉ Ferroelectric Thin Films At Low Temperature, Pingxiong Yang, David L. Carroll, John Ballato, Robert W. Schwartz
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The temperature dependence of electrical properties for SrBi2Ta2O9 thin film capacitors with platinum electrodes (Pt/SBT/Pt) on silicon wafers was studied from 10 to 300 K. with a decrease in temperature from 300 to 200 K, the remanent polarization of the thin films shows about an 11% reduction from its 300 K value; however, it is reduced by about 87% reduction from its 200 K value when the temperature drops from 200 to 100 K. with a decrease to 200 K, the polarization fatigue was significant, and the capacitor shows an approximate 29% reduction in polarization from its initial value following …
System Integration And Real-Time Control Architecture Of A Laser Aided Manufacturing Process, Mallikharjuna R. Boddu, Robert G. Landers, Srinivas Musti, Sanjeev Agarwal, Jianzhong Ruan, Frank W. Liou
System Integration And Real-Time Control Architecture Of A Laser Aided Manufacturing Process, Mallikharjuna R. Boddu, Robert G. Landers, Srinivas Musti, Sanjeev Agarwal, Jianzhong Ruan, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This paper discusses a hybrid deposition–removal manufacturing system being developed at the University of Missouri--Rolla. The system consists of a laser system, five-axis CNC machining center, and powder feeder system. A description of the control software, real-time control architecture, and integration of various subsystems to build the hybrid system is given. The interaction of the real-time controller with various sensors and subsystems to monitor and regulate the process is presented. The communication between integrated process planning for the system and real–time control is also discussed in this paper.
Optical Limiting In Srbi₂Ta₂O₉ And Pbzrxti₁₋ₓo₃ Thin Films, Pingxiong Yang, Jianfeng Xu, Robert W. Schwartz, David L. Carroll, John Ballato
Optical Limiting In Srbi₂Ta₂O₉ And Pbzrxti₁₋ₓo₃ Thin Films, Pingxiong Yang, Jianfeng Xu, Robert W. Schwartz, David L. Carroll, John Ballato
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Optical limiting effects in SrBi2Ta2O9 (SBT) and PbZrxTi1-xO3 (PZT) ferroelectric thin films have been observed with nanosecond laser pulses at 1.064 µm. Limiting thresholds were found to be 5.84 J/cm2 for SBT and between 4.53 and 5.93 J/cm2 for PZT, depending on composition, whereas saturation thresholds for the films were about 2.92 J/cm2 and between 2.27 J/cm2 to 2.97 J/cm2, respectively. Damage thresholds around 10.0 J/cm2 and between 10.37 J/cm2 to 10.54 J/cm2, respectively for SBT and PZT, were also determined. A possible mechanism for the observed limiting, nonlinear optical scattering from the ferroelectric domains, is discussed. These results elucidate …
Network Formalism For Modeling Functionally Gradient Piezoelectric Plates And Stacks And Simulations Of Rainbow Ceramic Actuators, Robert W. Schwartz, A. Ballato, John Ballato
Network Formalism For Modeling Functionally Gradient Piezoelectric Plates And Stacks And Simulations Of Rainbow Ceramic Actuators, Robert W. Schwartz, A. Ballato, John Ballato
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A simple network representation is given for a stack of thin, homogeneous piezoelectric plates, executing a single thickness mode of motion. All plates may differ in thickness and material properties, including dielectric loss, ohmic conductivity, and viscous loss. Each plate is driven by a thickness-directed electric field, and all stack elements are connected electrically in series. Functionally gradient single plates and composites are readily modeled by the network, to a desired precision, using a sequence of circuit elements representing stepwise variations in material properties and layer thicknesses. Simulations of RAINBOW (reduced and internally biased oxide wafer) ceramics are given.
Dynamics Of Poly(Vinyl Acetate)-D₃ On Silica, Robert D. O'Connor, Frank D. Blum, Gu Xu
Dynamics Of Poly(Vinyl Acetate)-D₃ On Silica, Robert D. O'Connor, Frank D. Blum, Gu Xu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Poly(vinyl acetate) (PVAc) is an important polymer in applications because of both its bulk and surface characteristics. Its chain architecture gives it a low Tg and, generally, good qualities for processing and applications, which include paints, adhesives, thin films and surface coatings. In this study, we investigate the surface dynamics of PVAc absorbed onto silica with deuterium nuclear magnetic resonance (2H NMR). For dynamics studies, 2H NMR is an excellent technique because it uses an innocuous probe that can report on correlation times (τc) from approximately 10-8 s to 10 s. We report the use of two-dimensional exchange NMR (2D-X) …
Development Of Transparent Lsco And Lscno Conductors For Optical Shutter Systems, Robert W. Schwartz, M. T. Sebastian, M. Charoenwongsa, H. D. Dobberstein
Development Of Transparent Lsco And Lscno Conductors For Optical Shutter Systems, Robert W. Schwartz, M. T. Sebastian, M. Charoenwongsa, H. D. Dobberstein
Mechanical and Aerospace Engineering Faculty Research & Creative Works
We have prepared lanthanum strontium cobalt oxide (La0.50Sr0.50CoO3; LSCO 50/50) and lanthanum strontium cobalt nickel oxide (La0.50Sr0.50Co0.50Ni0.50O3; LSCNO) as candidate transparent electrodes for use in a shutter-based infrared sensor protection device. The shutter device requires that the electrode be transparent (80% transmission) and have moderate sheet resistance (300 Ω/sq.). Because of the effects of film thickness on intrinsic material properties, such as resistivity and extinction coefficient, and simple engineering issues (i.e., the relationship between film thickness, resistance and transmission), films of various thicknesses were prepared to achieve an optimal balance of electrical and optical performance. van der Pauw measurements and …
Evaluation Of Lsco Electrodes For Sensor Protection Devices, Robert W. Schwartz, M. T. Sebastian
Evaluation Of Lsco Electrodes For Sensor Protection Devices, Robert W. Schwartz, M. T. Sebastian
Mechanical and Aerospace Engineering Faculty Research & Creative Works
We have evaluated lanthanum strontium cobalt oxide (La0.50Sr0.50CoOx; LSCO 50/50) as a candidate “transparent” electrode for use in an electrostatic shutter-based infrared sensor protection device. The device requires that the electrode be transparent (80% transmission) and have moderate sheet resistance (300 - 500 Ω/sq.). To meet these needs, the effects of postdeposition annealing on the resistivity and optical absorption characteristics of sputter deposited LSCO thin films were studied. The as-deposited films were characterized by an absorption coefficient of ~ 12,500 cm-1 and resistivities of ~ 0.08 to 0.5 Ω-cm. With annealing at 800°C, the resistivity decreased to 350 μΩ-cm, while …
Grain Oriented Crystallization, Piezoelectric, And Pyroelectric Properties Of (Baxsr₂ - X)Tisi₂O₈ Glass Ceramics, Jianping Zhang, Burtrand I. Lee, Robert W. Schwartz, Zhenya Ding
Grain Oriented Crystallization, Piezoelectric, And Pyroelectric Properties Of (Baxsr₂ - X)Tisi₂O₈ Glass Ceramics, Jianping Zhang, Burtrand I. Lee, Robert W. Schwartz, Zhenya Ding
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Polar, nonferroelectric (BaxSr2 - x)TiSi2O8 glass ceramics with highly oriented crystallites were prepared by a gradient temperature heat treatment technique. The crystallization mechanism and microstructures of (BaxSr2 - x)TiSi2O8 glass ceramics were investigated by means of differential thermal analysis, x-ray diffraction and scanning electron microscopy, and the dielectric, piezoelectric and pyroelectric properties were investigated for various compositions. The results show that polar (BaxSr2 - x)TiSi2O8 glass ceramics have a low dielectric constant and a high hydrostatic figure of merit dh × gh = ~ 2500. This high hydrostatic figure of merit, along with other unique characteristics, such as no aging …
Metal-Organic Chemical Vapor Deposition Of Sr-Co-Fe-O Films On Porous Substrates, C.-F. Xia, P. Atanasova, Robert W. Schwartz, T. L. Ward
Metal-Organic Chemical Vapor Deposition Of Sr-Co-Fe-O Films On Porous Substrates, C.-F. Xia, P. Atanasova, Robert W. Schwartz, T. L. Ward
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Aerosol-assisted chemical vapor deposition using the b-diketonate precursors Sr(tmhd)2•2H2O, Fe(tmhd)3 and Co(tmhd)3 was investigated for depositing thin films of the mixed-conducting ceramic SrCoyFe1-yO3-d onto porous a-Al2O3 substrates. Single-phase SrCoyFe1-yO3-d perovskite films were obtained at a deposition temperature of 550°C and pressure of 15 mm Hg, whereas deposition at atmospheric pressure produced mixed-phase films. The Co/Fe elemental ratios in the films reflected those in the precursor solution, but the films were depleted in Sr. Reduced-pressure deposition provided a more uniform film morphology than atmospheric-pressure, and led to a supported film which was leak-tight to N2 flow.
Elasto-Composition Waves In Inhomogeneous Solids, R. C. Batra, Manfred Wuttig
Elasto-Composition Waves In Inhomogeneous Solids, R. C. Batra, Manfred Wuttig
Mechanical and Aerospace Engineering Faculty Research & Creative Works
No abstract provided.