scholarly journals Formation and Growth of Intermetallic Compounds during Reactions between Liquid Gallium and Solid Nickel

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5694
Author(s):  
Doyoung Lee ◽  
Chang-Lae Kim ◽  
Yoonchul Sohn
Keyword(s):  
Intermetallic Compounds ◽  
Liquid Metals ◽  
Electronic Devices ◽  
Interface Reaction ◽  
Vertical Direction ◽  
Bottom Layer ◽  
Liquid Gallium ◽  
Mechanical Reliability ◽  
Metal Electrodes ◽  
Solid Nickel

Liquid metals, such as Ga and eutectic Ga-In, have been extensively studied for various applications, including flexible and wearable devices. For applying liquid metal to electronic devices, interconnection with the various metal electrodes currently in use, and verifying their mechanical reliability are essential. Here, detailed investigations of the formation and growth of intermetallic compounds (IMCs) during the reactions between liquid Ga and solid nickel were conducted. Ga and Ni were reacted at 250, 300, and 350 °C for 10–240 min. The IMC double layer observed after the reactions contained a Ga7Ni3 bottom layer formed during the reactions, and a GaxNi top layer (with 89–95 at.% of Ga) precipitated during cooling. Numerous empty channels exist between the rod-type Ga7Ni3 IMCs. Ga7Ni3 growth occurred only in the vertical direction, without lateral coarsening and merging between the rods. The time exponents were measured at 1.1–1.5, implying that the reaction kinetics were near-interface reaction-controlled. The activation energy for Ga7Ni3 growth was determined as 49.1 kJ/mol. The experimental results of the Ga-Ni reaction study are expected to provide important information for incorporating liquid metals into electronic devices in the future.

scholarly journals Mechanochemical synthesis of intermetallic compounds in the system gallium – ruthenium

2021 ◽  
Vol 8 (1) ◽  
pp. 20218104
Author(s):  
T. F. Grigoreva ◽  
E. A. Pavlov ◽  
P. A. Vitiaz ◽  
N. Z. Lyakhov
Keyword(s):  
Mechanical Activation ◽  
Intermetallic Compounds ◽  
Liquid Metals ◽  
High Energy ◽  
Complex Compounds ◽  
Liquid Gallium ◽  
X Ray Diffraction ◽  
X Ray ◽  
Active Metal ◽  
Surface Active

The interaction of a solid inert metal Ru with liquid active metal Ga during mechanical activation in a high-energy planetary ball mill was studied using the X-ray diffraction and the high resolution scanning electron microscopy with energy dispersive X-ray microanalyses. This paper considers mechanical activation effects on formation of intermetallic compounds GaxRuy and their solubility in concentrated acids. Gallium is a surface-active substance with respect to Ruthenium. Under intensive mechanical treatment, liquid Gallium penetrates into grain boundaries of polycrystalline Ruthenium particles and sharply reduces their strength. Because of severe mechanical deformation, an intensive increase of contact surface between solid and liquid metals observed, which a place of rapid formation of intermetallic compounds. This processing leads to high reactive products of mechanical activation of Ga + Ru. Their interaction with a mixed concentrated hydrochloric and nitric acid allows Ruthenium (~37%) to pass into an acidic solution, forming complex compounds of the HxRuCly type (H2RuCl6).

Convective Cooling of Compact Electronic Devices via Liquid Metals with Low Melting Points

2021 ◽  
Author(s):  
Guilin Liu ◽  
Jing Liu
Keyword(s):  
Heat Transfer ◽  
Melting Point ◽  
Liquid Metal ◽  
High Performance ◽  
Flow Resistance ◽  
Heat Dissipation ◽  
Liquid Metals ◽  
Electronic Devices ◽  
Convective Cooling ◽  
Heat Exchanger Design

Abstract The increasingly high power density of today's electronic devices requires the cooling techniques to produce highly effective heat dissipation performance with as little sacrifice as possible to the system compactness. Among the currently available thermal management schemes, the convective liquid metal cooling provides considerably high performance due to their unique thermal properties. This paper firstly reviews the studies on convective cooling using low-melting-point metals published in the past few decades. A group of equations for the thermophysical properties of In-Ga-Sn eutectic alloy is then documented by rigorous literature examination, following by a section of correlations for the heat transfer and flow resistance calculation to partially facilitate the designing work at the current stage. The urgent need to investigate the heat transfer and flow resistance of forced convection of low-melting-point metals in small/mini-channels, typical in compact electronic devices, is carefully argued. Some special aspects pertaining to the practical application of this cooling technique, including the entrance effect, mixed convection, and compact liquid metal heat exchanger design, are also discussed. Finally, future challenges and prospects are outlined.

scholarly journals Freeze Frames vs. Movies

2014 ◽  
Vol 70 (a1) ◽  
pp. C178-C178
Author(s):  
Carola Müller ◽  
Sven Lidin
Keyword(s):  
Intermetallic Compounds ◽  
Degrees Of Freedom ◽  
Model Building ◽  
Electronic Devices ◽  
Atomic Arrangement ◽  
Modulation Wave ◽  
Structure Solution ◽  
Methodological Errors ◽  
In The Beginning ◽  
Lock In

Sometimes, model building in crystallography is like resolving a puzzle: All obvious symmetrical or methodological errors are excluded, you apparently understand the measured patterns in 3D, but the structure solution and/or refinement is just not working. One such nerve-stretching problem arises from metrically commensurate structures (MCS). This expression means that the observed values of the components of the modulation wave vectors are rational by chance and not because of a lock-in. Hence, it is not a superstructure - although the boundaries between the two descriptions are blurry. Using a superstructure model for a MCS decreases the degrees of freedom, and forces the atomic arrangement to an artificial state of ordering. Just imagine it as looking at a freeze frame from a movie instead of watching the whole film. The consequences in structure solution and refinement of MCS are not always as dramatically as stated in the beginning. On the contrary, treating a superstructure like a MCS might be a worthwhile idea. Converting from a superstructure model to a superspace model may lead to a substantial decrease in the number of parameters needed to model the structure. Further, it can permit for the refinement of parameters that the paucity of data does not allow in a conventional description. However, it is well known that families of superstructures can be described elegantly by the use of superspace models that collectively treat a whole range of structures, commensurate and incommensurate. Nevertheless, practical complications in the refinement are not uncommon. Instances are overlapping satellites from different orders and parameter correlations. Notably, MCS occur in intermetallic compounds that are important for the performance of next-generation electronic devices. Based on examples of their (pseudo)hexagonal 3+1D and 3+2D structures, we will discuss the detection and occurrence of MCS as well as the benefits and limitations of implementing them artificially.

scholarly journals Development of Real-Time Measurement Platform for Stretchable and Rollable Functions of Flexible Electronics under Multiple Dynamic Loads

Micromachines ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 106
Author(s):  
Chang-Chun Lee ◽  
Jui-Chang Chuang ◽  
Ruei-Ci Shih ◽  
Chi-Wei Wang
Keyword(s):  
Flexible Electronics ◽  
Electronic Devices ◽  
Sine Wave ◽  
Wearable Devices ◽  
Dynamic Loads ◽  
Inspection System ◽  
Mechanical Reliability ◽  
Electronic Components ◽  
Real Time Measurement ◽  
Applied Fields

Mainstream next generation electronic devices with miniaturized structures and high levels of performance are needed to meet the characteristic requirements of electronics with flexible and stretchable capabilities. Accordingly, several applied fields of innovative electronic component techniques, such as wearable devices, foldable curtain-like displays, and flexible hybrid electronic (FHE) biosensors, are considered. This study presents a novel inspection system with multifunctions of stressing tensile and bending mechanical loads to acquire the stretchable and rollable characteristics of soft specimens. The performance of the proposed measurement platform using samples of three different geometric types is evaluated in terms of its stretchability. The results show a remarkable enhancement of mechanical reliability when the sine wave geometric structure is used. A symmetrical sine wave-shaped sample is designed to measure performance under cyclic rolling. The proposed measurement platform of flexible electronics meets the testing requirements of mechanical reliability for the development of future flexible electronic components and FHE products.

scholarly journals CostNet: A Concise Overpass Spatiotemporal Network for Predictive Learning

2020 ◽  
Vol 9 (4) ◽  
pp. 209
Author(s):  
Fengzhen Sun ◽  
Shaojie Li ◽  
Shaohua Wang ◽  
Qingjun Liu ◽  
Lixin Zhou
Keyword(s):  
State Of The Art ◽  
Vertical Direction ◽  
Bottom Layer ◽  
Spatiotemporal Data ◽  
Short Term ◽  
The Core ◽  
Predictive Learning ◽  
Fast Gradient ◽  
Unit Output ◽  
Cross Connection

Predicting the futures from previous spatiotemporal data remains a challenging topic. There have been many previous works on predictive learning. However, mainstream models suffer from huge memory usage or the gradient vanishing problem. Enlightened by the idea from the resnet, we propose CostNet, a novel recursive neural network (RNN)-based network, which has a horizontal and vertical cross-connection. The core of this network is a concise unit, named Horizon LSTM with a fast gradient transmission channel, which can extract spatial and temporal representations effectively to alleviate the gradient propagation difficulty. In the vertical direction outside of the unit, we add overpass connections from unit output to the bottom layer, which can capture the short-term dynamics to generate precise predictions. Our model achieves better prediction results on moving-mnist and radar datasets than the state-of-the-art models.

Miscellaneous Applications of Intermetallic Compounds

MRS Bulletin ◽  
1996 ◽  
Vol 21 (5) ◽  
pp. 50-55 ◽  
Author(s):  
L.McD. Schetky
Keyword(s):  
Intermetallic Compounds ◽  
Metal Matrix ◽  
Heat Storage ◽  
Storage Systems ◽  
Electronic Devices ◽  
Matrix Composites ◽  
Gold Alloys ◽  
Dental Amalgams ◽  
Property Modification ◽  
Nuclear Applications

So ubiquitous are intermetallic compounds (IMCs) in all areas of materials application that examples of their use in industrial, medical, consumer, and military products are almost limitless. We will in this brief discussion attempt to identify some of the more important of these applications, which we categorize as miscellaneous. These include shape-memory alloys (SMAs), gold alloys used in jewelry, dental amalgams, tribology applications, diffusion barriers in electronic devices, elevated-heat storage systems, nuclear applications, metal-matrix composites, and high damping alloys. In some cases, the IMC is present as a precipitate or dispersed particle that provides strengthening or other property modification while in other examples, the IMC is employed in bulk form.

The embedded atom model for liquid metals: Liquid gallium and bismuth

2006 ◽  
Vol 80 (4) ◽  
pp. 509-522 ◽  
Author(s):  
D. K. Belashchenko ◽  
O. I. Ostrovskii
Keyword(s):  
Liquid Metals ◽  
Liquid Gallium ◽  
Atom Model ◽  
Embedded Atom

Electrical bistability in a composite of polymer and barium titanate nanoparticles

2009 ◽  
Vol 367 (1905) ◽  
pp. 4227-4234 ◽  
Author(s):  
I. Salaoru ◽  
S. Paul
Keyword(s):  
Electrical Conductivity ◽  
Barium Titanate ◽  
Organic Molecules ◽  
Electronic Devices ◽  
Organic Polymer ◽  
Memory Devices ◽  
Data Retention ◽  
Metal Electrodes ◽  
Small Organic Molecules ◽  
Barium Titanate Nanoparticles

Growth in the use of organic materials in the fabrication of electronic devices is on the rise. Recently, some attempts have been undertaken to manufacture polymer memory devices. Such devices are fabricated by depositing a blend (an admixture of organic polymer, small organic molecules and nanoparticles) between two metal electrodes. These devices show two electrical conductivity states (‘high’ and ‘low’) when a voltage is applied, thus rendering the structures suitable for data retention. In this paper, we describe an attempt to fabricate memory devices using ferroelectric nanoparticles embedded in an organic polymer. This paper also discusses issues related to the observed memory effect.

Numerical Simulation of Artificial Purification System by Using Hydrostatic and FULL-3D Combined Model

2003 ◽  
Author(s):  
Tsuguki Kinoshita ◽  
Shigeru Tabeta ◽  
Masataka Fujino
Keyword(s):  
Numerical Simulation ◽  
Dynamic Pressure ◽  
Vertical Direction ◽  
Bottom Layer ◽  
Momentum Equation ◽  
3D Analysis ◽  
Combined System ◽  
Purification System ◽  
Hydrostatic Approximation ◽  
Mixed Water

Ohmura bay is a typical enclosed estuary located in Kyushu, Japan. In the summer season, strong stratification is formed which brings oxygen-dificient water mass in the bottom layer. For the purpose of restoring water quality in the bay, field experiment of an artificial purification system was carried out. In the experiment, a diffusion pump was installed on the bottom of the bay. The instrument draws in the surface water of lower density and rich oxygen, mixes it with the bottom water of higher density and poor oxygen, and diffuses the mixed water upward. The mixed water is expected to spread along the isopycnic as density current, which will cause resolution of anoxic water in the bottom layer and promote the circulation of nutrients. However, it cannot be said the experiment was successful, and detail analysis by numerical simulation should be necessary in order to design more effective purification system. Most of ocean models employ the hydrostatic approximation because the horizontal scale is usually much larger than the vertical scale in oceanic phenomena. In the hydrostatic approximation, dynamic pressure is neglected and momentum equation of vertical direction need not to be solved. But in the present case, around the purification system, hydrodynamic pressure is not negligible and momentum equation of vertical direction must to be solved (called FULL-3D here). In FULL-3D calculation the time of calculation is much longer compared with using hydrostatic approximation. It is almost impossible to calculate the flow of the whole Ohmura bay by FULL-3D approach. The authors developed a new type of ocean model for multi-scale analysis, which conducts hydrostatic analysis for phenomena in wide area and FULL-3D analysis for the detail flow around the interesting object simultaneously. In order to connect the hydrostatic region and FULL-3D region, nested grid system is employed. Using this combined system, the effect of purification system to the whole bay will be investigated accurately.

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