We give thanks to the financial support of the National Natural Science Foundation of China (11076109), the Hong Kong Scholars Program (XJ2014045, G-YZ67), the "1000 Talents Plan" of the Sichuan Province, the Talent Introduction Program of Sichuan University (YJ201410), and the Innovation and Creative Experiment Program of Sichuan University (20171060, 20170133).

1. Preparation of the Raw Materials
<ol>
	<li>Weigh all the required raw materials with an electronic scale by mass percentage (65% electrolytic Mn, 26% electrolytic Cu, 2% industrial pure Fe, 2% electrolytic Ni, 3% electrolytic Al, and 2% electrolytic Zn), as shown in Figure 1. 
	&#8203;NOTE: All these raw materials were commercially available.</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/57180/57180fig1.jpg" /> 
Figure 1: Presentation of raw materials. The materials used include 65 wt% electrolytic Mn, 26 wt% electrolytic Cu, 2 wt% industrial pure Fe, 2 wt% electrolytic Ni, 2 wt% electrolytic Zn, and 3 wt% electrolytic Al. <a href="https://www.jove.com/files/ftp_upload/57180/57180fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
2. Melting and Casting Process
NOTE: The detailed steps of sand casting are shown in Figure 2.
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/57180/57180fig2.jpg" /> 
Figure 2: Sand casting and molding steps. The main process includes pattern-making, mold-making, and a casting operation. <a href="https://www.jove.com/files/ftp_upload/57180/57180fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<ol>
	<li>To prepare patterns, make patterns according to the product drawing, and make sure that the size of the pattern is expanded to a certain extent to be liable for shrinkage and machining allowances. 
	NOTE: The pattern material used in this work is wood ( Figure 3) because a wood pattern is light, easy to work, and has a low cost and short production cycle.</li>
</ol>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/57180/57180fig3.jpg" /> 
Figure 3: Patterns used in the casting mold. These wood patterns were used to obtain the shape of the castings. <a href="https://www.jove.com/files/ftp_upload/57180/57180fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<ol start="2">
	<li>To prepare the molding sand, mix together the quartz sand with 4% - 8% sodium silicate. 
	NOTE: The sand diameter is about 0.4 mm and the particles are uniform.</li>
	<li>Complete the main molding process by hands.
	<ol>
		<li>First, put two patterns in the molding flask.</li>
		<li>Then, roll over the flask after ramming the molding sand around the patterns and withdraw the patterns from the sand.</li>
		<li>Finally, brush the surface of the sand mold with casting coating for improving the casting surface quality and reducing casting defects. 
		&#8203;NOTE: The molded sand mold is shown in Figure 4.</li>
		<li>To obtain a dry sand mold, put the mold in an oven at 180 &#176;C and bake it for more than 8 h before casting to enhance its strength and permeability, facilitate the melt filling, and ensure the quality of the casting products.</li>
	</ol>
	</li>
</ol>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/57180/57180fig4.jpg" /> 
Figure 4: The molded sand mold. It has two cavities and its surface has been covered with a coating. <a href="https://www.jove.com/files/ftp_upload/57180/57180fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
3. Induction of Melting
NOTE: Use a medium-frequency vacuum induction melting furnace.
<ol>
	<li>Open the furnace lid, put 20.8 kg of Mn, 8.32 kg of Cu, 0.64 kg of Ni, 0.64 kg of Fe, 0.64 kg of Zn, and 0.96 kg of Al materials in the crucible successively, and cover the materials with cryolite at last.</li>
	<li>Take out the casting mold from the oven and put it in the furnace; adjust its position for a successful pouring. Close the lid, vacuum the furnace, and then open the heat distribution system to start melting the alloy.</li>
	<li>When the metals start to melt, fill the furnace with argon to a 93-KPa negative pressure, to inhibit the splashing of the molten metal.</li>
	<li>After the alloy has melted, refine it for several minutes to reduce the harmful impurities and gas content. 
	NOTE: The melting procedure often includes smelting and refining.</li>
</ol>
4. Casting the Alloy
<ol>
	<li>Pour the molten metal smoothly into the casting mold after the refining process.</li>
	<li>After the molten metal is completely solidified, break the vacuum and take out the casting mold.</li>
	<li>Remove the castings from the casting mold when the temperature of the mold drops to a low level.</li>
</ol>
5. Pretreatment of the Castings
NOTE: The macrophotograph of the molded part is shown in Figure 5.
<ol>
	<li>Cut specimens from the casting by using a linear cutting machine. 
	&#8203;NOTE: The specimens for the X-ray diffractometer (XRD) measurements and the metallographic observation are in 10 x 10 x 1 mm3. The specimens for the dynamic thermomechanical analysis (DMA) possess a dimension of 0.8 x 10 x 35 mm3.</li>
</ol>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/57180/57180fig5.jpg" /> 
Figure 5: The molded parts in the sand mold and the removed parts. Two castings were molded at one time. <a href="https://www.jove.com/files/ftp_upload/57180/57180fig5large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
6. Heat Treatment
<ol>
	<li>Divide the polished specimens into seven groups and keep specimen #1 free of treatment, maintaining an as-cast state for comparison. Put the others in a box-type resistance oven for different heat treatments.</li>
	<li>Homogenize specimens #2 and #5 at 850 &#176;C for 24 h and, subsequently, quench them in cool water before aging them at 435 &#176;C, specimen #2 for 4 h and specimen #5 for 2 h.</li>
	<li>Solution-treat specimens #3 and #6 at 900 &#176;C for 1 h and, subsequently, quench them in cool water before aging them at 435 &#176;C, specimen #3 for 4 h and specimen #6 for 2 h.</li>
	<li>Age specimens #4 and #7 at 435 &#176;C for 4 h and 2 h, respectively.</li>
</ol>
7. Damping Capacity Test
<ol>
	<li>Use a Dynamic Mechanical Analysis (DMA) to measure the damping capacity of the specimens17. 
	NOTE: The test mode is strain sweep at room temperature.</li>
	<li>During the test, detect the phase angle &#948; between the stress and the strain (as shown in Figure 6).</li>
	<li>Characterize the damping capacity by Q-1, which can be determined by the following formula. 
	Q-1&#160;= Tan&#160;&#948;</li>
</ol>
<img alt="Figure 6" class="xfigimg" src="/files/ftp_upload/57180/57180fig6.jpg" /> 
Figure 6: The fixture construction and testing principle of the DMA. ( a) This panel shows the double cantilever fixture of the DMA. ( b) This panel shows the relationship of the applied sinusoidal stress to the strain and the resultant phase lag. The values of the lag between the stress and the strain, as well as the modulus, can be calculated by formulae. <a href="https://www.jove.com/files/ftp_upload/57180/57180fig6large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
8. Sample Characterization
<ol>
	<li>Electrolytic polishing and metallographic observation
	<ol>
		<li>For a dendrite microstructure observation, etch all specimens for about 1 min in a mixed solution of perchloric acid and absolute alcohol at 1:27.</li>
		<li>Then, clean the specimens with acetone, dry the sample with a blower, and observe the dendritic structure with a metallographic microscope.</li>
	</ol>
	</li>
	<li>Phase structure characterization
	<ol>
		<li>Characterize the phase structure and the lattice parameters of the specimens by X-ray diffraction (XRD) with CuK&#945; radiation12,22. 
		NOTE: Use a scan speed at 2&#176;/min. Before the XRD measurement, prepare the specimens carefully by removing any surface stress.</li>
	</ol>
	</li>
</ol>

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The authors have nothing to disclose.

To ensure that this kind of as-cast Mn-Cu-based alloy possesses both&#160;superior damping capacity and excellent mechanical properties, it is necessary to ensure that the castings have a stable chemical composition, a high purity, and an excellent crystal structure. Therefore, strict quality control is necessary for the smelting, pouring, and heat treatment processes.
Firstly, it is necessary to choose the proper ingredients for the alloy. It should be considered that the added alloy elements...

Since the Mn-Cu alloys were found by Zener to have&#160;damping capacity1, they have received widespread attention and research2. The advantages of Mn-Cu alloy are that it has&#160;high damping capacity, especially at low strain amplitudes, and its damping capacity cannot be disturbed by a magnetic field, which is quite different from ferromagnetic damping alloys. The high damping capacity of Mn-Cu-based alloys can be mainly attributed to the movability of the internal boundaries, mainly including twin boundaries and phase boundaries, which are generated in the face-centered-cubic-to-face-centered-tetragonal (f.c.c.-f.c.t.) phase transition under the martensite transformation temperature (Tt)3. It has been found that Tt depends directly on the Mn content in the Mn-Cu-based alloy4,5; that is, the higher the Mn content, the higher the Tt and the better the damping capacity of the material. The alloy, which contains more than 80 at% manganese, was found to have&#160;high damping capacity and optimum strength when quenched from the solid-solution temperature6. However, the higher Mn concentration in the alloy would directly cause the alloy to be more brittle and have a lower elongation, impact toughness, and a worse corrosion resistance, which means the alloy will not meet the engineering requirements. Previous research findings revealed that an aging treatment under suitable conditions is an effective way to reconcile this problem; for instance, Mn-Cu-based damping alloys containing 50 - 80 at% Mn can also obtain a high Tt and&#160;favorable damping capacity by an aging treatment in the appropriate temperature range7. This is due to the decomposition of the &#947;-parent phase into nanoscale Mn-rich regions and nanoscale Cu-rich regions while aging in the temperature range of the miscibility gap8,9,10, which is considered to improve Tt of this alloy along with its damping capacity. Clearly, it is an effectual method which can combine&#160;high damping capacity with excellent workability.
M2052 alloy used for forging forming, a representative Mn-Cu-based high-damping alloy with medium Mn content developed by Kawahara et al.11, has been extensively studied in the last few decades. Researchers found that M2052 alloy has a good sweet spot between damping capacity, yield strength, and workability. Compared with the forging technique, casting has been widely used so far due to the simple molding process, low production costs, and high productivity, etc. The influential factors (e.g., oscillation frequency, strain amplitude, cooling velocity, heat treatment temperature/time, etc.) on the damping capacity, microstructure, and damping mechanism of M2052 alloy have been studied by some researchers12,13,14,15,16,17,18. Nevertheless, the casting performance of M2052 alloy is inferior, for instance, a wide range of crystallization temperature, the occurrence of casting porosity, and concentrated shrinkage, eventually resulting in the unsatisfactory mechanical properties of the castings.
The purpose of this paper is to provide the industrial field with a feasible method of obtaining a cast Mn-Cu based alloy with excellent properties which can be used in machinery and in the precision instruments industry to reduce vibration and ensure the product quality. According to the effect of alloying elements on the phase transformation and the casting performance, Al element is considered to reduce the &#947;-phase region and the stability of the &#947; phase, which can make the &#947; phase more easily transform into a &#947;&#39; phase with micro-twins. Moreover, the solution of Al atoms in the &#947; phase will increase the strength of the alloy, which can improve the mechanical properties. Also, Al element is one of the important elements which can improve the casting properties of Mn-Cu alloy. Zn element is beneficial to improving the casting and damping properties of the alloy. Finally, 2 wt% Zn and 3 wt% Al were added to the MnCuNiFe quaternary alloy in this work and a new cast Mn-26Cu-12Ni-2Fe-2Zn-3Al (wt%) alloy was developed. Furthermore, several different heat treatment methods are used in this work and their distinct effects are discussed as follows. The homogenization treatment was used to reduce dendrite segregation. The solution treatment was used for impurities immobilization. The aging treatment is used for triggering spinodal decomposition; meanwhile, the various aging times are used for seeking out the optimizing parameters for both excellent damping capacity and a high service temperature. Ultimately, a preferable heat treatment method was screened for superior damping capacity, as well as a high service temperature.
It turns out that the maximum internal friction (Q-1) and the highest service temperature can be achieved concurrently by aging the alloy at 435 &#176;C for 2 h. Because of the simplicity and efficiency of this preparation method, a novel as-cast Mn-Cu-based damping alloy with excellent performance can be produced, which is of important practical significance for its engineering application. This method is particularly suitable for the preparation of casting Mn-Cu-based high damping alloy which can be used for vibration reduction.

<table border="0" cellpadding="0" cellspacing="0" style="width:747px;" width="747">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:163px;">manganese</td>
			<td style="width:299px;">Daye Nonferrous Metals Group Holdings Co., Ltd.</td>
			<td style="width:119px;">DJMnB</td>
			<td style="width:167px;">produced by electrolysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:163px;">copper</td>
			<td>Daye Nonferrous Metals Group Holdings Co., Ltd.</td>
			<td style="width:119px;">Cu-CATH-2</td>
			<td>produced by electrolysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:163px;">Nickel</td>
			<td>Daye Nonferrous Metals Group Holdings Co., Ltd.</td>
			<td>Ni99.99</td>
			<td>produced by electrolysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Iron</td>
			<td style="width:299px;">Ningbo Jiasheng Metal Materials Co., Ltd.</td>
			<td>YT01</td>
			<td>industrial pure Fe</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Zinc</td>
			<td>Daye Nonferrous Metals Group Holdings Co., Ltd.</td>
			<td>0#</td>
			<td>produced by electrolysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Aluminum</td>
			<td>Daye Nonferrous Metals Group Holdings Co., Ltd.</td>
			<td>Al99.90</td>
			<td>produced by electrolysis</td>
		</tr>
	</tbody>
</table>

an available technique for preparation of new cast mncunifeznal alloy with superior damping capacity and high service temperature

Manganese (Mn)-copper (Cu)-based alloys have been found to have&#160;damping capacity and can be used to reduce harmful vibrations and noise effectively. M2052 (Mn-20Cu-5Ni-2Fe, at%) is an important branch of Mn-Cu-based alloys, which possesses both excellent damping capacity and processability. In recent decades, lots of studies have been carried out on the performance optimization of M2052, improving the damping capacity, mechanical properties, corrosion resistance, and service temperature, etc. The major methods of performance optimization are alloying, heat treatment, pretreatment, and different ways of molding etc., among which alloying, as well as adopting a reasonable heat treatment, is the simplest and most effective method to obtain perfect and comprehensive performance. To obtain the M2052 alloy with excellent performance for casting molding, we propose to add Zn and Al to the MnCuNiFe alloy matrix and use a variety of heat treatment methods for a comparison in the microstructure, damping capacity, and service temperature. Thus, a new type of cast-aged Mn-22.68Cu-1.89Ni-1.99Fe-1.70Zn-6.16Al (at.%) alloy with&#160;superior damping capacity and high service temperature is obtained by an optimized heat treatment method. Compared with the forging technique, cast molding is simpler and more efficient, and the damping capacity of this as-cast alloy is excellent. Therefore, there is a suitable reason to think that it is a good choice for engineering applications.

Figure 7&#160;shows the dependency of the damping capacity on the strain amplitude for the as-cast MnCuNiFeZnAl alloy specimens #1 - #7 and as-cast M2052. The results show that the damping capacity of specimen #1 is higher than that of cast M2052 alloy (as shown in Figure 7a) and the traditional forged M2052 high-damping alloy mentioned in previous articles20,21. Moreover...

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An Available Technique for Preparation of New Cast MnCuNiFeZnAl Alloy with Superior Damping Capacity and High Service Temperature

Here we present a protocol to obtain a novel Mn-Cu-based alloy with excellent comprehensive performances by a high-quality smelting technology and reasonable heat treatment methods.

Manganese (Mn)-copper (Cu)-based alloys have been found to have&#160;damping capacity and can be used to reduce harmful vibrations and noise effectively. ...

an-available-technique-for-preparation-new-cast-mncunifeznal-alloy

Research

JoVE Journal

Engineering

6.8K Views.  Sichuan University. Here we present a protocol to obtain a novel Mn-Cu-based alloy with excellent comprehensive performances by a high-quality smelting technology and reasonable heat treatment methods. 

Video: An Available Technique for Preparation of New Cast MnCuNiFeZnAl Alloy with Superior Damping Capacity and High Service Temperature

Synthesis and Microdiffraction at Extreme Pressures and Temperatures

High pressure compounds and polymorphs are investigated for a broad range of purposes such as determine structures and processes of deep planetary interiors, design materials with novel properties, understand the mechanical behavior of materials exposed to very high stresses as in explosions or impacts. Synthesis and structural analysis of materials at extreme conditions of pressure and temperature entails remarkable technical challenges. In the laser heated diamond anvil cell (LH-DAC), very high pressure is generated between the tips of two opposing diamond anvils forced against each other; focused infrared laser beams, shined through the diamonds, allow to reach very high temperatures on samples absorbing the laser radiation. When the LH-DAC is installed in a synchrotron beamline that provides extremely brilliant x-ray radiation, the structure of materials under extreme conditions can be probed in situ. LH-DAC samples, although very small, can show highly variable grain size, phase and chemical composition. In order to obtain the high resolution structural analysis and the most comprehensive characterization of a sample, we collect diffraction data in 2D grids and combine powder, single crystal and multigrain diffraction techniques. Representative results obtained in the synthesis of a new iron oxide, Fe4O5 1 will be shown.

The laser heated diamond anvil cell combined with synchrotron micro-diffraction techniques allows researchers to explore the nature and properties of new phases of matter at extreme pressure and temperature (PT) conditions. Heterogeneous samples can be characterized in situ under high pressure by 2D mapping and combined powder, single-crystal and multigrain diffraction approaches.

High pressure compounds and polymorphs are investigated for a broad range of purposes such as determine structures and processes of deep planetary ...

Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive thin-films. Due to the low growth temperature, the process allows integration with modern low-&#954; dielectrics and some flexible substrates. The process is compatible with standard semiconductor fabrication, and a method for the fabrication of electrical 4-point probe test structures for vertical interconnect test structures is presented. Using scanning electron microscopy the morphology of the CNT bundles is investigated, which demonstrates vertical alignment of the CNT and can be used to tune the CNT growth time. With Raman spectroscopy the crystallinity of the CNT is investigated. It was found that the CNT have many defects, due to the low growth temperature. The electrical current-voltage measurements of the test vertical interconnects displays a linear response, indicating good ohmic contact was achieved between the CNT bundle and the top and bottom metal electrodes. The obtained resistivities of the CNT bundle are among the average values in the literature, while a record-low CNT growth temperature was used.

A method for the growth of low temperature vertically-aligned carbon nanotubes, and the subsequent fabrication of vertical interconnect electrical test structures using semiconductor fabrication is presented.

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive ...

Fiber Optic Distributed Sensors for High-resolution Temperature Field Mapping

The reliability of computational fluid dynamics (CFD) codes is checked by comparing simulations with experimental data. A typical data set consists chiefly of velocity and temperature readings, both ideally having high spatial and temporal resolution to facilitate rigorous code validation. While high resolution velocity data is readily obtained through optical measurement techniques such as particle image velocimetry, it has proven difficult to obtain temperature data with similar resolution. Traditional sensors such as thermocouples cannot fill this role, but the recent development of distributed sensing based on Rayleigh scattering and swept-wave interferometry offers resolution suitable for CFD code validation work. Thousands of temperature measurements can be generated along a single thin optical fiber at hundreds of Hertz. Sensors function over large temperature ranges and within opaque fluids where optical techniques are unsuitable. But this type of sensor is sensitive to strain and humidity as well as temperature and so accuracy is affected by handling, vibration, and shifts in relative humidity. Such behavior is quite unlike traditional sensors and so unconventional installation and operating procedures are necessary to ensure accurate measurements. This paper demonstrates implementation of a Rayleigh scattering-type distributed temperature sensor in a thermal mixing experiment involving two air jets at 25 and 45 &#176;C. We present criteria to guide selection of optical fiber for the sensor and describe installation setup for a jet mixing experiment. We illustrate sensor baselining, which links readings to an absolute temperature standard, and discuss practical issues such as errors due to flow-induced vibration. This material can aid those interested in temperature measurements having high data density and bandwidth for fluid dynamics experiments and similar applications. We highlight pitfalls specific to these sensors for consideration in experiment design and operation.

We demonstrate use of a fiber optic distributed sensor for mapping the temperature field of mixing air jets. The Rayleigh scattering-based sensor generates thousands of data points along a single fiber to provide exceptional spatial resolution that is unattainable with traditional sensors such as thermocouples.

The reliability of computational fluid dynamics (CFD) codes is checked by comparing simulations with experimental data. A typical data set consists ...

Applying X-ray Imaging Crystal Spectroscopy for Use as a High Temperature Plasma Diagnostic

X-ray spectra provide a wealth of information on high temperature plasmas; for example electron temperature and density can be inferred from line intensity ratios. By using a Johann spectrometer viewing the plasma, it is possible to construct profiles of plasma parameters such as density, temperature, and velocity with good spatial and time resolution. However, benchmarking atomic code modeling of X-ray spectra obtained from well-diagnosed laboratory plasmas is important to justify use of such spectra to determine plasma parameters when other independent diagnostics are not available. This manuscript presents the operation of the High Resolution X-ray Crystal Imaging Spectrometer with Spatial Resolution (HIREXSR), a high wavelength resolution spatially imaging X-ray spectrometer used to view hydrogen- and helium-like ions of medium atomic number elements in a tokamak plasma. In addition, this manuscript covers a laser blow-off system that can introduce such ions to the plasma with precise timing to allow for perturbative studies of transport in the plasma.

X-ray spectra provide a wealth of information on high temperature plasmas. This manuscript presents the operation of a high wavelength resolution spatially imaging X-ray spectrometer used to view hydrogen- and helium-like ions of medium atomic number elements in a tokamak plasma.

X-ray spectra provide a wealth of information on high temperature plasmas; for example electron temperature and density can be inferred from line ...

Adsorption Device Based on a Langatate Crystal Microbalance for High Temperature High Pressure Gas Adsorption in Zeolite H-ZSM-5

We present a high-temperature and high-pressure gas adsorption measurement device based on a high-frequency oscillating microbalance (5 MHz langatate crystal microbalance, LCM) and its use for gas adsorption measurements in zeolite H-ZSM-5. Prior to the adsorption measurements, zeolite H-ZSM-5 crystals were synthesized on the gold electrode in the center of the LCM, without covering the connection points of the gold electrodes to the oscillator, by the steam-assisted crystallization (SAC) method, so that the zeolite crystals remain attached to the oscillating microbalance while keeping good electroconductivity of the LCM during the adsorption measurements. Compared to a conventional quartz crystal microbalance (QCM) which is limited to temperatures below 80 &#176;C, the LCM can realize the adsorption measurements in principle at temperatures as high as 200-300 &#176;C (i.e., at or close to the reaction temperature of the target application of one-stage DME synthesis from the synthesis gas), owing to the absence of crystalline-phase transitions up to its melting point (1,470 &#176;C). The system was applied to investigate the adsorption of CO2, H2O, methanol and dimethyl ether (DME), each in the gas phase, on zeolite H-ZSM-5 in the temperature and pressure range of 50-150 &#176;C and 0-18 bar, respectively. The results showed that the adsorption isotherms of these gases in H-ZSM-5 can be well fitted by Langmuir-type adsorption isotherms. Furthermore, the determined adsorption parameters, i.e., adsorption capacities, adsorption enthalpies, and adsorption entropies, compare well to literature data. In this work, the results for CO2 are shown as an example.

A protocol for high-temperature and high-pressure gas adsorption measurements on zeolite H-ZSM-5 using an adsorption measurement device based on a langatate crystal microbalance is presented. Prior to the adsorption measurements, the synthesis of zeolite H-ZSM-5 on the langatate crystal microbalance sensor by the steam-assisted crystallization (SAC) method is demonstrated.

We present a high-temperature and high-pressure gas adsorption measurement device based on a high-frequency oscillating microbalance (5 MHz langatate ...

Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature

The chemical instability of the traditional electrolyte remains a safety issue in widely used energy storage devices such as Li-ion batteries. Li-ion batteries for use in devices operating at elevated temperatures require thermally stable and non-flammable electrolytes. Ionic liquids (ILs), which are non-flammable, non-volatile, thermally stable molten salts, are an ideal replacement for flammable and low boiling point organic solvent electrolytes currently used today. We herein describe the procedures to: 1) synthesize mono- and di-phosphonium ionic liquids paired with chloride or bis(trifluoromethane)sulfonimide (TFSI) anions; 2) measure the thermal properties and stability of these ionic liquids by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA); 3) measure the electrochemical properties of the ionic liquids by cyclic voltammetry (CV); 4) prepare electrolytes containing lithium bis(trifluoromethane)sulfonamide; 5) measure the conductivity of the electrolytes as a function of temperature; 6) assemble a coin cell battery with two of the electrolytes along with a Li metal anode and LiCoO2 cathode; and 7) evaluate battery performance at 100 &#176;C. We additionally describe the challenges in execution as well as the insights gained from performing these experiments.

Here, we describe protocols to prepare phosphonium-based ionic liquid and lithium bis(trifluoromethane)sulfonimide salt electrolytes, and assemble a non-flammable and high temperature functioning lithium-ion coin cell battery.

The chemical instability of the traditional electrolyte remains a safety issue in widely used energy storage devices such as Li-ion batteries. Li-ion ...

Experimental Procedure for Warm Spinning of Cast Aluminum Components

High performance, cast aluminum automotive wheels are increasingly being incrementally formed via flow forming/metal spinning at elevated temperatures to improve material properties. With a wide array of processing parameters which can affect both the shape attained and resulting material properties, this type of processing is notoriously difficult to commission. A simplified, light-duty version of the process has been designed and implemented for full-size automotive wheels. The apparatus is intended to assist in understanding the deformation mechanisms and the material response to this type of processing. An experimental protocol has been developed to prepare for, and subsequently perform forming trials and is described for as-cast A356 wheel blanks. The thermal profile attained, along with instrumentation details are provided. Similitude with full-scale forming operations which impart significantly more deformation at faster rates is discussed.

An experimental protocol for instrumented warm rotary forming of cast aluminum alloys employing a bespoke industrially scaled apparatus is presented. Experimental considerations including thermal and mechanical effects are discussed, as well as similitude with full-scale processing of automotive wheels.

High performance, cast aluminum automotive wheels are increasingly being incrementally formed via flow forming/metal spinning at elevated temperatures to ...

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia (YSZ) Scaffolds by In Situ Carbon Templating Xerogels

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) scaffolds with tunable specific surface areas up to 80 m2&#183;g-1. An aqueous solution of a zirconium salt, yttrium salt, and glucose is mixed with propylene oxide (PO) to form a gel. The gel is dried under ambient conditions to form a xerogel. The xerogel is pressed into pellets and then sintered in an argon atmosphere. During sintering, a YSZ ceramic phase forms and the organic components decompose, leaving behind amorphous carbon. The carbon formed in situ serves as a hard template, preserving a high surface area YSZ nanomorphology at sintering temperature. The carbon is subsequently removed by oxidation in air at low temperature, resulting in a porous, nanostructured YSZ scaffold. The concentration of the carbon template and the final scaffold surface area can be systematically tuned by varying the glucose concentration in the gel synthesis. The carbon template concentration was quantified using thermogravimetric analysis (TGA), the surface area and pore size distribution was determined by physical adsorption measurements, and the morphology was characterized using scanning electron microscopy (SEM). Phase purity and crystallite size was determined using X-ray diffraction (XRD). This fabrication approach provides a novel, flexible platform for realizing unprecedented scaffold surface areas and nanomorphologies for ceramic-based electrochemical energy conversion applications, e.g. solid oxide fuel cell (SOFC) electrodes.

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels

A protocol for fabricating porous, nanostructured yttria-stabilized-zirconia (YSZ) scaffolds at temperatures between 1,000 &#176;C and 1,400 &#176;C is presented.

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) ...

Preparation and High-temperature Anti-adhesion Behavior of a Slippery Surface on Stainless Steel

Anti-adhesion surfaces with high-temperature resistance have a wide application potential in electrosurgical instruments, engines, and pipelines. A typical anti-wetting superhydrophobic surface easily fails when exposed to a high-temperature liquid. Recently, Nepenthes-inspired slippery surfaces demonstrated a new way to solve the adhesion problem. A lubricant layer on the slippery surface can act as a barrier between the repelled materials and the surface structure. However, the slippery surfaces in previous studies rarely showed high-temperature resistance. Here, we describe a protocol for the preparation of slippery surfaces with high-temperature resistance. A photolithography-assisted method was used to fabricate pillar structures on stainless steel. By functionalizing the surface with saline, a slippery surface was prepared by adding silicone oil. The prepared slippery surface maintained the anti-wetting property for water, even when the surface was heated to 300 &#176;C. Also, the slippery surface exhibited great anti-adhesion effects on soft tissues at high temperatures. This type of slippery surface on stainless steel has applications in medical devices, mechanical equipment, etc.

Slippery surfaces provide a new way to solve the adhesion problem. This protocol describes how to fabricate slippery surfaces at high temperatures. The results demonstrate that the slippery surfaces showed anti-wetting for liquids and a remarkable anti-adhesion effect on soft tissues at high temperatures.

Anti-adhesion surfaces with high-temperature resistance have a wide application potential in electrosurgical instruments, engines, and pipelines. A ...

Magnet Assisted Composite Manufacturing: A Flexible New Technique for Achieving High Consolidation Pressure in Vacuum Bag/Lay-Up Processes

This work demonstrates a protocol to improve the quality of composite laminates fabricated by wet lay-up vacuum bag processes using the recently developed magnet assisted composite manufacturing (MACM) technique. In this technique, permanent magnets are utilized to apply a sufficiently high consolidation pressure during the curing stage. To enhance the intensity of the magnetic field, and thus, to increase the magnetic compaction pressure, the magnets are placed on a magnetic top plate. First, the entire procedure of preparing the composite lay-up on a magnetic bottom steel plate using the conventional wet lay-up vacuum bag process is described. Second, placement of a set of Neodymium-Iron-Boron permanent magnets, arranged in alternating polarity, on the vacuum bag is illustrated. Next, the experimental procedures to measure the magnetic compaction pressure and volume fractions of the composite constituents are presented. Finally, methods used to characterize microstructure and mechanical properties of composite laminates are discussed in detail. The results prove the effectiveness of the MACM method in improving the quality of wet lay-up vacuum bag laminates. This method does not require large capital investment for tooling or equipment and can also be used to consolidate geometrically complex composite parts by placing the magnets on a matching top mold positioned on the vacuum bag.

A new technique for applying consolidation pressure on the vacuum bag lay-up to fabricate composite laminates is described. The goal of this protocol is to develop a simple, cost-effective technique to improve the quality of laminates fabricated by the wet lay-up vacuum bag method.

This work demonstrates a protocol to improve the quality of composite laminates fabricated by wet lay-up vacuum bag processes using the recently developed ...