Engineering Commons^™

Surface Acoustic Wave Spectroscopy Versus Nanoindentation: Potentials And Limits For Coating Characterization, Martin Zawischa, Dieter Schneider, Stefan, Makowski, Lars Lorenz

Nanomechanical Testing in Materials Research and Development VII

Measuring mechanical film properties is essential for understanding and designing coating systems as well for controlling quality in coating manufacturing. Since more than two decades, two methods for determining Young’s modulus and other mechanical properties of thin films are widely used: The instrumented indentation technique (nanoindentation) and the laser-induced surface acoustic wave spectroscopy (LiSAWS). Due to their different physical principles, both methods address different fields of application but also complement each other. This presentation gives an overview for typical applications, strengths and limits for both methods from practical points of view like precision, requirements for sample material, preparation and test …

Effect Of Anisotropic Elasticity On Dislocation Pile-Ups At Grain Boundaries, Xiaolei Chen, Stéphane Berbenni, Christian Motz, Thiebaud Richeton

Nanomechanical Testing in Materials Research and Development VII

This study deals with in-situ micromechanical tests of micron-sized bi-crystals and observations coupling SEM, AFM and EBSD. Different FCC bi-crystals are obtained from FIB machining. A SEM in-situ compression test with a low strain is performed on a micron-sized bi-crystal in order to induce single slip deformation. Spatial variations in the surface step height due to dislocation activity in localized slip bands terminating at the grain boundary (GB) are measured by AFM. This allows the determination of the Burgers vector distribution and hence the dislocation positions in the pile-up as shown in Figure 1. Furthermore, local misorientation along slip bands …

Conference Program, Jon Molina-Aldareguia

Nanomechanical Testing in Materials Research and Development VII

No abstract provided.

Performance Enhancement Of Ssi-Leds And Geometrically Confinement Of Lighting Dots By Using Patterned Wafer Approaches, Shengli Wu, Yiwei Liu, Xiaoning Zhang, Can Yang, Lingguang Liu, Yaogong Wang, Gang Niu

Semiconductor Technology for Ultra Large Scale Integrated Circuits and Thin Film Transistors VII (ULSIC VS TFT 7)

Solid state incandescent light emitting devices (SSI-LEDs) were first demonstrated in 2013 by Kuo’s group, which have the metal-oxide-semiconductor structure and emit white light directly¹. The conductive filaments (CFs) through CAFM figures out that Si wafer has a significant impact on the device performance^{2, 3}, multiplayer dielectric layers structure have also been study to enhance the light emission⁴. We demonstrate two approaches to improve the performance of SSI-LEDs by using patterned wafer in this work.

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Ulsi And Tft Technologies In Industry, Research And Higher Education In France: An Evolution Towards Innovation Resulting From Close And Sustainable Interaction, Olivier Bonnaud

Semiconductor Technology for Ultra Large Scale Integrated Circuits and Thin Film Transistors VII (ULSIC VS TFT 7)

The semiconductor industry and associated microelectronic production began in France in the early 1980s as part of the national microelectronics plan launched by the French government to meet the needs of new economic sectors that are heavy users of microelectronic products. Indeed, microelectronic circuits, devices and systems are the key elements of the information technology field, which includes computer and communications capabilities, and application fields such as aerospace, transport, and energy, mainly. Several new technologies had to be developed, corresponding to the first advent of communication tools such as Minitel (ancestor of the web) or credit cards, which then underwent …

Conference Program, Yue Kuo, Junichi Murota, Yasuhiro Fukunaka, Yukiharu Uraoka

Semiconductor Technology for Ultra Large Scale Integrated Circuits and Thin Film Transistors VII (ULSIC VS TFT 7)

No abstract provided.

Ultra-Rapid Microwave Sintering Of Ceramics And Powder Metals, Kirill I. Rybakov, Yury Bykov, Anatoly Eremeev, Sergei Egorov, Vladislav Kholoptsev, Ivan Plotnikov, Andrei Sorokin

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

Over the recent years, we have demonstrated ultra-rapid microwave sintering of different ceramic materials, including Al₂O₃, ZrO₂, Y₂O₃, MgAl₂O₄, and Yb:(LaO)₂O₃, using a gyrotron system operating at a frequency of 24 GHz with an output microwave power of up to 6 kW [1-3]. The ceramic pellets were sintered to 98-99.5 % of the theoretical density with the duration of the high-temperature sintering stage not exceeding several minutes. We have shown that the absorbed microwave power required for the ultra-rapid sintering regimes is …

Effect Of The Addition Of Doped-Cobalt On The Properties Of Recycled Tungsten Carbide Powder Sintered By Sps, Alexandre Mégret, Véronique Vitry, Fabienne Delaunois

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

A key issue that has appeared in the last twenty years is the availability of certain materials. Cobalt is considered as a critical raw material since it is massively used in batteries for electrical cars [1]. Cobalt is also the usual binder in cemented carbides because it gives excellent hardness to toughness ratio at the tungsten carbide parts. There is a tendency to replace cobalt by other binders such nickel or iron [2] but cobalt remains the best one. Recycling old WC parts is a solution to limit the use of raw cobalt powder and to keep the benefits of …

Kinetics Of Liquid-Assisted Densification During Flash Sintering Of Ceramic Nanoparticles, Rachman Chaim

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

The recent liquid film capillary mechanism [1, 2] proposed for the rapid densification during the flash sintering was consistent energetically with the dissipated power during the process. Following this mechanism, melting of contacts with high electric resistance will induce high attractive capillary forces. Wetting of a solid substrate by its own melt is termed homologous wetting with zero wetting (dihedral) angle. Therefore, wetting and spreading of the melt on its own substrate is extremely fast. Here we will show that particle surface softening / melting and the following transient processes associated with it namely local melt wetting and spreading, particle …

Advantages Of The Method Of High-Voltage Consolidation Of Powder Materials, Evgeny Grigoryev, Vladimir Goltsev, Natalya Ermakova, Andrey Osintsev, Aleksandr Plotnikov

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

The main features of high-voltage electropulse consolidation (H-VEC) of powder materials and the unique possibilities of the method caused by them are considered. The electro-thermal processes in the H-VEC at the contacts between the powder particles and in the macroscale of the whole consolidated sample are analyzed. The results of calculations of the dynamics of closure (collapse) of interparticle pores in the consolidated material are presented. The experimental results of high voltage consolidation W-based heavy alloys are discussed and a theoretical analysis of the kinetics of compaction of powder materials is made. The results of investigation of the macro- and …

Flash Sintering Of Beta-Alumina Solid Electrolytes For Sodium Battery Applications, Gareth Jones, Y. Hu, S. Ghanizadeh, D. Pearmain, S.N. Heavens, J.S. Blackburn, S. Maclachlan

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

The rechargeable sodium batteries, sodium sulphur (NaS) batteries and molten-salt sodium nickel chloride (Na-NiCl₂) are proven commercially available systems, particularly for large-scale energy storage applications and electric vehicle applications respectively. They have attractive properties such as the use of abundant low-cost raw materials, high energy and power density, high faradaic efficiency of charge/discharge, zero self-discharge rate and proven long-term durability. Conventional manufacturing of the core component, the sodium beta”-alumina solid electrolyte, requires a high sintering temperatures, ~ 1600 °C to achieve high density and good ceramic quality, which contributes significantly to battery cost, energy and time consumption in …

Field Assisted Sintering Of Larger Scaled Ceramic Parts Using Adapted Tool Design And Hybrid Heating, Martin Bram, Moritz Kindelmann, Alexander M. Laptev, Olivier Guillon

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

Field Assisted Sintering/Spark Plasma Sintering (FAST/SPS) is a promising technology for the energy efficient sintering of ceramic, composite and metal powders. The combination of direct current heating and applied pressure enables high heating rates, rapid densification and offers the potential to decrease the sintering temperature significantly. FAST/SPS is of special interest for materials, which are difficult to densify by conventional methods like pressure less sintering. To establish this processing technology on industrial scale, fundamental studies are required to better understand the relationship between processing parameters, specific FAST/SPS boundary conditions and resulting material properties. A challenging task – especially for non-conductive …

Hybrid Sintering – The Beneficial Combination Of Sintering Principles, Juergen Hennicke, Tobias Kessel, Sergio Rivera Monte

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

„Hybrid Sintering“ can be defined as a beneficial combination of different sintering principles, e.g. direct and indirect heating, uniaxial and gas pressure, high and low electrical fields (Figure 1). In the technological context this can be completed by debindering, decoupled pre-heating and cooling as well as rate controlled sintering optionally. Hybrid sintering systems enable the development and production of all new material solutions.

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Conference Program, Rishi Raj, Olivier Guillon, Hidehiro Yoshida

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

No abstract provided.

Photoluminescence In Sps-Processed Transparent Ce:Yag Ceramics, Avital Wagner, Nachum Frage, Sergey Kalabukhov, Barak Ratzker

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

Ceramic phosphors display great promise for the realization of high-power lighting devices. Cerium-doped yttrium aluminum garnet (Ce:YAG) is commonly used as a phosphor in white light emitting diodes. Therefore, it was chosen as a case study to investigate photoluminescence of transparent ceramic phosphors fabricated by spark plasma sintering (SPS). In the present work, 0.5 at.% Ce:YAG nano-powder was synthesized by a co-precipitation method and subsequently consolidated by SPS into highly transparent ceramic samples. The effect of varying sintering parameters (temperature and pressure) and post-sintering treatments (hot isostatic pressing and air atmosphere thermal treatment) on optical properties was investigated. Correlations between …

Β-Sialon-Based Ceramic Composites By Combustion Synthesis And Spark Plasma Sintering, Evgeny Grigoryev, Vladimir Goltsev, Konstantin Smirnov, Dmitriy Moskovskikh, Aleksey Sedegov

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

Spark-plasma sintering (SPS) of composite ceramics in the β-Si₅AlON₇– system (SiC, TiN, BN) was studied. An effective mechanism of intensification of sintering processes was revealed due to the introduction of h-BN, having a scaly structure and playing the role of a solid lubricant, which improves the compressibility of the sintered powder mixtures under load. For composites containing 0–30 wt. % h-BN, 0–40 wt.% β-SiC, and 0–40 wt. % TiN, with different character distribution of components by volume (homogeneous, layered and gradient), the optimal parameters of the PCA were established, ensuring the achievement of a high level …

Tensile Strength Of Materials Obtained By Electric Pulse Consolidation Of Powders, Evgeny Grigoryev, Vladimir Goltsev, Andrey Osintsev, Aleksandr Plotnikov

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

A wide range of products of modern technology, obtained by electropulse consolidation of powders, has dimensions that do not exceed 10-15 mm in diameter, and their thickness varies from 1 to 10 mm. Standard mechanical testing methods for such sample sizes are often not applicable.

The article investigates the possibility of determining the resistance to fracture of materials obtained from powders by electric pulse consolidation method using the test method for bending thin disks on an annular support and testing short cylinders according to the "Brazilian test". A numerical simulation of the process of bending a thin disk on an …

Microstructure Evolution During High-Pressure Spark Plasma Sintering (Hpsps) Of Transparent Alumina, Barak Ratzker, Sergey Kalabukhov, Nachum Frage, Avital Wagner

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

Applying high-pressure during spark plasma sintering (so-called HPSPS) enables rapid densification of a ceramic powder at relatively lower temperatures, limiting grain growth and allowing fabrication of fine-grained highly transparent ceramics. The present work focuses on the fabrication of fine submicron transparent alumina from untreated commercial powder by HPSPS and the microstructure evolution during consolidation under high applied pressure. The sintering was conducted at relatively low temperatures (1000-1100°C) under high pressure varied from 250 to 800 MPa. We review unique sintering phenomena such as stress-enhanced grain growth and de-sintering, which are related to creep taking place during the final stage of …