Unusual Wetting Behavior of Liquid Metals on Porous Layer Formed at Surface of Iron Substrate Prepared by Oxidation-Reduction Process

2007 ◽  
Vol 561-565 ◽  
pp. 1699-1701
Author(s):  
Nobuyuki Takahira ◽  
Takeshi Yoshikawa ◽  
Toshihiro Tanaka

Unusual wetting behavior of liquid Cu was found on a surface-oxidized iron substrate in reducing atmosphere. Liquid Cu wetted and spread very widely on the iron substrate when a droplet was attached with the substrate in Ar-10%H2 after the surface oxidation of the substrate. The oxidationreduction process fabricates a porous layer at the surface of the iron substrate. The pores in the porous iron layer are 3-dimensionally interconnected. Thus, liquid metals, which are contacted with the reduced iron samples, penetrate into these pores by capillary force to cause the unusual wetting behavior. It has been already confirmed that liquid Ag, Sn, In and Bi show this phenomenon onto surface-porous iron samples as well as liquid Cu. This unusual wetting behavior of a liquid metal has been correlated to the normal contact angle of the liquid metal on a flat iron substrate.

Nanoscale ◽  
2021 ◽  
Author(s):  
Hiroki Ota ◽  
Nyamjargal Ochirkhuyag ◽  
Ryosuke Matsuda ◽  
Zihao Song ◽  
Fumika Nakamura ◽  
...  

Research on liquid metals has been steadily garnering more interest in recent times because the properties of these metals are conducive to flexible electronics applications; further, these metals are in...


2013 ◽  
Vol 23 (2) ◽  
pp. 137-137 ◽  
Author(s):  
Vijay Sivan ◽  
Shi-Yang Tang ◽  
Anthony P. O'Mullane ◽  
Phred Petersen ◽  
Nicky Eshtiaghi ◽  
...  
Keyword(s):  

Author(s):  
A. Lipchitz ◽  
Lilian Laurent ◽  
G. D. Harvel

Several Generation IV nuclear reactors, such as sodium fast reactors and lead-bismuth fast reactors, use liquid metal as a coolant. In order to better understand and improve the thermal hydraulics of liquid metal cooled GEN IV nuclear reactors liquid metal flow needs to be studied in experimental circulation loops. Experimental circulation loops are often located in a laboratory setting. However, studying liquid metal two phase flow in laboratory settings can be difficult due to the high temperatures and safety hazards involved with traditional liquid metals such as sodium and lead-bismuth. One solution is to use a low melt metal alloy that is as benign as reasonably achievable. Field’s metal is a eutectic alloy of 51% Indium, 32.5% Bismuth and 16.5% Tin by weight and has a melting point of 335K making it ideal for use in a laboratory setting. A study is undertaken to determine its suitability to use in a two-phase experimental flow loop enhanced by magnetohydrodynamic forces. The study investigated its reactivity with air and water, its ability to be influenced by magnetic fields, its ability to flow, and its ease of manufacture. The experiments melted reference samples of Field’s metal and observed its behaviour in a glass beaker, submerged in water and an inclined stainless steel pipe. Then Field’s metal was manufactured in the laboratory and compared to the sample using the same set of experiments and standards. To determine Field’s metal degree of magnetism permanent neodymium magnets were used. Their strength was determined using a Gaussmeter. All experiments were recorded using a COHU digital camera. Image analysis was then performed on the video to determine any movements initiated by the magnetic field forces. In conclusion, Field’s metal is more than suitable for use in experimental settings as it is non-reactive, non-toxic, simple to manufacture, easy to use, and responds to a magnetic force.


2021 ◽  
pp. 2151037
Author(s):  
Yu Meng ◽  
Qing Zhong ◽  
Arzugul Muslim

Because −NH2 and −NH− in poly-[Formula: see text]-phenylenediamine (P[Formula: see text]PD) can interact strongly with the empty orbitals of Cu to show unique electrochemical activity, P[Formula: see text]PD is suitable for the removal of Cu[Formula: see text] by electrochemical oxidation–reduction process. In this study, with P[Formula: see text]PD and its carbon dot composite (CDs/P[Formula: see text]PD) as working electrodes, the electrochemical reduction and removal of Cu[Formula: see text] in the aqueous solution were carried out with the potentiostatic method. According to effects of voltage, pH of the solution, initial concentration of Cu[Formula: see text], and electrochemical reduction time on the Cu[Formula: see text] removal, the Cu[Formula: see text] removal ratios of P[Formula: see text]PD and CDs/P[Formula: see text]PD were up to 64.69% and 73.34%, respectively, at −0.2 V and the optimal pH. Additionally, results showed that these processes were in line with the quasi-first order kinetic model. Both P[Formula: see text]PD and CDs/P[Formula: see text]PD showed good reproducibility in six cycles. After five times of repeated usage, the regeneration efficiencies of P[Formula: see text]PD and CDs/P[Formula: see text]PD dropped to 77.04% and 79.36%, respectively.


2021 ◽  
Author(s):  
Guilin Liu ◽  
Jing Liu

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.


2016 ◽  
Vol 48 (9) ◽  
pp. 969-972
Author(s):  
Hiroshi Takano ◽  
Masafumi Hiraishi ◽  
Shigeru Yaguchi ◽  
Satoru Iwata ◽  
Shin-ichiro Shoda ◽  
...  

Author(s):  
Gopinath R. Warrier ◽  
Y. Sungtaek Ju ◽  
Jan Schroers ◽  
Mark Asta ◽  
Peter Hosemann

In response to the DOE Sunshot Initiative to develop low-cost, high efficiency CSP systems, UCLA is leading a multi-university research effort to develop new high temperature heat transfer fluids capable of stable operation at 800°C and above. Due to their operating temperature range, desirable heat transfer properties and very low vapor pressure, liquid metals were chosen as the heat transfer fluid. An overview of the ongoing research effort is presented. Development of new liquid metal coolants begins with identification of suitable candidate metals and their alloys. Initial selection of candidate metals was based on such parameters as melting temperature, cost, toxicity, stability/reactivity Combinatorial sputtering of the down selected candidate metals is used to fabricate large compositional spaces (∼ 800), which are then characterized using high-throughput techniques (e.g., X-ray diffraction). Massively parallel optical methods are used to determine melting temperatures. Thermochemical modeling is also performed concurrently to compliment the experimental efforts and identify candidate multicomponent alloy systems that best match the targeted properties. The modeling effort makes use of available thermodynamic databases, the computational thermodynamic CALPHAD framework and molecular-dynamics simulations of molten alloys. Refinement of available thermodynamics models are performed by comparison with available experimental data. Characterizing corrosion in structural materials such as steels, when using liquid metals, and strategies to mitigate them are an integral part of this study. The corrosion mitigation strategy we have adopted is based on the formation of stable oxide layers on the structural metal surface which prevents further corrosion. As such oxygen control is crucial in such liquid metal systems. Liquid metal enhanced creep and embrittlement in commonly used structural materials are also being investigated. Experiments with oxygen control are ongoing to evaluate what structural materials can be used with liquid metals. Characterization of the heat transfer during forced flow is another key component of the study. Both experiments and modeling efforts have been initiated. Key results from experiments and modeling performed over the last year are highlighted and discussed.


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