scholarly journals Research on the Physical Characteristics of Hot-Pressed Sintering Preparing Self-Fluxing Filler by X-Ray Diffraction

2021 ◽  
Vol 2083 (2) ◽  
pp. 022087
Author(s):  
Xiupeng Li ◽  
Weimin Long ◽  
Yuanxun Shen ◽  
Sujuan Zhong ◽  
Yinyin Pei ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Joint Strength ◽  
Filler Metal ◽  
Low Cost ◽  
Metal Ring ◽  
Joint Interface ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metal Rings ◽  
Al Matrix

Abstract In this paper, Al-12Si self-fluxing filler metal ring was prepared with Al-12Si alloying powders and KAlF4 flux by hot pressed sintering (HPS) method. The microstructure and mechanical properties of the brazing alloy and the brazed 3003 aluminum alloy joint were investigated. The results showed that Al-12Si self-fluxing filler metal ring could be successfully obtained by HPS at 470°C using a pressure of 300MPa. The prepared filler metal ring was dense and defect-free and the microstructure was mainly composed of Si phase with KAlF4 flux grain uniformly distributed in the Al matrix. The 3003 aluminum alloy joint interface brazed by the prepared filler metal was also well bonded and no pore and defect was found. A quite high joint strength of 75MPa was obtained which is equal to the strength of joint brazed using commercial Al-Si self-fluxing wires prepared by hot extrude method. The results revealed that the filler metal rings fabricated by HPS process had great potentiality in brazing of aluminum alloy especially for the Al-Al pipes joining due to its high joint strength, low cost and the convenience for industrial application.

scholarly journals Investigation on Strength and Microstructural Evolution of Porous Cu/Cu Brazed Joints Using Cu-Ni-Sn-P Filler

Metals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 416
Author(s):  
Mian Muhammad Sami ◽  
Tuan Zaharinie ◽  
Farazila Yusof ◽  
Tadashi Ariga
Keyword(s):  
Surface Hardening ◽  
Filler Metal ◽  
Joint Interface ◽  
X Ray Diffraction ◽  
Cooling Device ◽  
X Ray ◽  
Porous Copper ◽  
Brazed Joints ◽  
Increasing Temperature ◽  
Integral Feature

Porous Copper (Cu) was brazed to Cu plates using Cu-9.7Sn-5.7Ni-7P amorphous filler metal. The effects of brazing parameters on the porous Cu and brazed joints were investigated. The furnace brazing temperatures employed were 660 °C and 680 °C, and the holding times were 10 and 15 min. After brazing, the microstructure was analyzed using Scanning Electron Microscope (SEM) equipped with Electron Dispersive X-ray Spectroscope (EDS). SEM results showed that the thickness of the brazed seam at the base joint decreased with increasing temperature and time. At low brazing temperature, microvoids and cracks were observed at the joint interface. The microvoids and cracks disappeared in the sample brazed at 680 °C for 15 min, and higher diffusion of the filler was noted in the overall bonded region. The formation of Cu-P, Cu-Ni, and Ni-Sn phases at the joint interface was validated using X-ray diffraction. The phases formed increased the hardness of the brazed joints and porous Copper. It was observed that the rigidity of porous Copper tends to increase due to surface hardening effects. The rigidity of porous Cu after brazing is important in ensuring minimal deformation during cooling device servicing, which is an integral feature of prospect product development.

scholarly journals Multidimensional Ln-Aminophthalate Photoluminescent Coordination Polymers

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1786
Author(s):  
Carla Queirós ◽  
Chen Sun ◽  
Ana M. G. Silva ◽  
Baltazar de Castro ◽  
Juan Cabanillas-Gonzalez ◽  
...  
Keyword(s):  
Water Content ◽  
Coordination Polymers ◽  
Metal Ion ◽  
Low Cost ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wide Range ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.

Transient liquid phase bonding of Cu and Al using metallic particles interlayers

2021 ◽  
pp. 095440542098823
Author(s):  
Alireza Zaheri ◽  
Mohammadreza Farahani ◽  
Alireza Sadeghi ◽  
Naser Souri
Keyword(s):  
Liquid Phase ◽  
Mechanical Test ◽  
Transient Liquid Phase ◽  
Transient Liquid Phase Bonding ◽  
Joint Interface ◽  
Test Results ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metallic Particles ◽  
Powder Interlayer

The bonding strength, and microstructures of Cu and Al couples using metallic powders as interlayer during transient liquid phase bonding (TLP bonding) were investigated. The interfacial morphologies and microstructures were studied by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, and X-ray diffraction. First, to explore the optimum bonding time and temperature, nine samples were bonded without interlayers in a vacuum condition. Mechanical test results indicated that bonding at 560°C in 20 min returns the highest bond strength (84% of Al). This bonding condition was used to join ten samples with powder interlayers. Powders were prepared by mixing different combinations of Cu, Al (+Fe nanoparticles) and Zn. In the bonding zone, different Cu9Al4, CuAl, and CuAl2 intermetallic co-precipitate. The strongest bonding is formed in the sample with the 70Al (+Fe)-30Cu powder interlayer. Powder interlayers present thinner and more uniform intermetallic layers at the joint interface.

A simple and low-cost solution for the automation of X-ray powder diffractometers with chart recorder output

2006 ◽  
Vol 39 (4) ◽  
pp. 626-629
Author(s):  
M. Jayaprakasan ◽  
V. Kannan ◽  
P. Ramasamy
Keyword(s):  
Quantitative Analysis ◽  
Low Cost ◽  
Hard Copy ◽  
X Ray Diffraction ◽  
Raw Data ◽  
Crystalline Materials ◽  
X Ray ◽  
Strip Chart ◽  
Controlled Systems ◽  
Chart Recorder

X-ray powder diffraction is an established method for the qualitative identification of crystalline materials and their quantitative analysis. The new generation of X-ray diffraction systems are based on expensive digital/embedded control technology and computer interfaces. Yet many laboratories use conventional manual-controlled systems withXYstrip-chart recorders. Since the output spectrum is a strip chart (hard copy), raw data, essential for structural and qualitative analysis, are not readily available for further analysis. Upgrading to modern computerized diffractometers is very expensive. The proposed automation design described here is intended to enable the conventional diffractometer user to collect, store and analyze data quickly. The design also improves the resolution by five times compared with the conventional setup. For the automation, a PC add-on card has been designed to control and collect the timing and intensity counts from the conventional X-ray diffractometer, and suitable software has been developed to collect, process and present the X-ray diffraction data for both qualitative and quantitative analysis. Moreover, a major advantage of this design is that it does not warrant any physical modification of the hardware of the conventional setup; it is simply an extension to enhance the performance of collecting raw data with a higher resolution at desired intervals/timings.

Low-cost thermo-chemical process of TiO2 powder purification: Study of iterative gettering effect

2021 ◽  
Author(s):  
Nesrine Jaouabi ◽  
Wala Medfai ◽  
Marouan Khalifa ◽  
Rabia Zaghouani ◽  
Hatem Ezzaouia
Keyword(s):  
Porous Layer ◽  
Sacrificial Layer ◽  
Low Cost ◽  
Nir Spectroscopy ◽  
Tio2 Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Density Reduction ◽  
Transmission Electron ◽  
Layer Effect

The titanium dioxide (TiO2) purity is very important for the TiO2-based applications making essential the impurities density reduction. In this study, we propose an efficient purification process of TiO2 powder in order to reduce impurities. The low-cost proposed approach is based on an iterative gettering (IG) process combining three main steps: (1) a porous TiO2 sacrificial layer formation (p-TiO2), (2) a rapid thermal annealing (RTA) of p-TiO2 powder in an infrared oven at 950°C under air permitting the residual impurities diffusion to the porous layer surface and (3) etching in acid solution to remove the porous layer. Effect of the proposed gettering process on purification efficiency was evaluated by different characterization techniques such as the transmission electron microscopy (TEM), the energy dispersive x-ray spectroscopy (EDX), the UV–Visible-NIR spectroscopy, the X-ray diffraction (XRD) and atomic absorption spectroscopy (AAS). The obtained results showed the efficient removal of metal impurities, such as Cu, Al, P, and Fe confirming the efficiency of the process improving the purity from 89% to 99.96%.

scholarly journals Extraction of γ-Alumina from Low-Cost Kaolin

Resources ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 63
Author(s):  
Khalil Ibrahim ◽  
Mohammad Moumani ◽  
Salsabeela Mohammad
Keyword(s):  
Low Cost ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Aluminum Metal ◽  
Alumina Particles ◽  
Two Stages ◽  
Method Of Extraction ◽  
Microcrystalline Powder ◽  
Made In

A combined process is proposed for the utilization of local kaolin to produce alumina particles. The applied process is made in two stages: calcination at 700 °C with sodium chloride and leaching with sulfuric followed by hydrochloric acids. The optimal extraction efficiency can be obtained when the conditions are as follows: leaching temperature is at 140 °C, leaching time is 3 h 45 min and concentration of sulfuric acid is 40 wt.%. The results show that the purity of alumina reaches 79.28%, which is suitable for the production of aluminum metal. It is evident that this method of extraction of alumina from the kaolin ash is practical and feasible. The structural and morphological properties of the calcined microcrystalline powder was characterized by X-ray diffraction and scanning electron microscope (SEM).

scholarly journals Fast X-Ray Diffraction (XRD) Tomography for Enhanced Identification of Materials

2021 ◽  
Author(s):  
Airidas Korolkovas ◽  
Alexander Katsevich ◽  
Michael Frenkel ◽  
William Thompson ◽  
Edward Morton
Keyword(s):  
Graphics Processing Unit ◽  
Low Cost ◽  
Photon Counting ◽  
Finite Size ◽  
Processing Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Specific Material ◽  
Xrd Patterns ◽  
Graphics Processing

X-ray computed tomography (CT) can provide 3D images of density, and possibly the atomic number, for large objects like passenger luggage. This information, while generally very useful, is often insufficient to identify threats like explosives and narcotics, which can have a similar average composition as benign everyday materials such as plastics, glass, light metals, etc. A much more specific material signature can be measured with X-ray diffraction (XRD). Unfortunately, XRD signal is very faint compared to the transmitted one, and also challenging to reconstruct for objects larger than a small laboratory sample. In this article we analyze a novel low-cost scanner design which captures CT and XRD signals simultaneously, and uses the least possible collimation to maximize the flux. To simulate a realistic instrument, we derive a formula for the resolution of any diffraction pathway, taking into account the polychromatic spectrum, and the finite size of the source, detector, and each voxel. We then show how to reconstruct XRD patterns from a large phantom with multiple diffracting objects. Our approach includes a reasonable amount of photon counting noise (Poisson statistics), as well as measurement bias, in particular incoherent Compton scattering. The resolution of our reconstruction is sufficient to provide significantly more information than standard CT, thus increasing the accuracy of threat detection. Our theoretical model is implemented in GPU (Graphics Processing Unit) accelerated software which can be used to assess and further optimize scanner designs for specific applications in security, healthcare, and manufacturing quality control.

scholarly journals Construction and Mechanism of Bacterial Cellulose With High Carbon Yield By a Stretching Orientation Method

2021 ◽  
Author(s):  
Wenjing Jiang ◽  
Zhenlin Jiang ◽  
Xin Fan ◽  
Min Zhu
Keyword(s):  
Bacterial Cellulose ◽  
Low Cost ◽  
X Ray Diffraction ◽  
High Carbon ◽  
Carbon Yield ◽  
X Ray ◽  
Graphitization Degree ◽  
Low Field ◽  
Orientation Method ◽  
Environmentally Friendly Method

Abstract Bacterial cellulose (BC)decomposes easily and the carbon residue rate is low. These factors critically restrict its application in fabricating cellulosic carbon materials. Therefore, in this paper, a simple and facile method to improve the BC carbon yield is proposed based on the stretching orientation of BC. By controlling the degree of BC deformation, the orientation and crystallinity of the BC can be adjusted, thereby sensitively affecting the graphitization degree and carbon yield of carbonized BC. Samples were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), Raman scattering, and low-field nuclear magnetic resonance (LNMR). The results indicated that when the pre-stretched strain was 40%, the crystallinity and graphitization degree of BC improved, and the carbon yield increased significantly in comparison to that of untreated BC. Thus, a low-cost, facile, and environmentally friendly method of increasing the carbon yield of BC was developed in this study.

Effect of oxidation time on the microstructure and properties of ceramic coatings prepared by microarc oxidation on 7A04 superhard aluminum alloy

2017 ◽  
Vol 31 (16-19) ◽  
pp. 1744026
Author(s):  
Feng Xiao ◽  
Hui Chen ◽  
Jingguo Miao ◽  
Juan Du
Keyword(s):  
Aluminum Alloy ◽  
Microarc Oxidation ◽  
Ceramic Coatings ◽  
Ceramic Layer ◽  
X Ray Diffraction ◽  
Oxidation Treatment ◽  
X Ray ◽  
Metallurgical Bonding ◽  
Dense Ceramic ◽  
Morphology Of Surface

Under the sodium aluminates’ system, microarc oxidation treatment was conducted on the superhard aluminum alloy 7A04 for different times. The microstructure of microarc oxidation ceramic layer was investigated by using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The influences of different oxidation times on the adhesion strength of ceramic layer and substrate, the morphology of surface and cross-section, the phase composition and the electrochemical properties were studied. The results indicated that the connection of the coating and substrate appears to be metallurgical bonding and dense ceramic layer, and the surface is in a “volcanic vent” morphology, which is composed of [Formula: see text]-Al2O3 and little [Formula: see text]-Al2O3. The corrosion resistance of ceramic layer is improved significantly in contrast with that of the substrate.

scholarly journals Synthesis Fe3O4/Talc nanocomposite by coprecipition-ultrasonication method and advances in hexavalent chromium removal from aqueous solution

2020 ◽  
Vol 38 (9-10) ◽  
pp. 483-501
Author(s):  
Nguyen Thi Huong ◽  
Nguyen Ngoc Son ◽  
Vo Hoang Phuong ◽  
Cong Tien Dung ◽  
Pham Thi Mai Huong ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Adsorption Process ◽  
Low Cost ◽  
Batch Experiments ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Langmuir And Freundlich Equations

The Fe3O4/Talc nanocomposite was synthesized by the coprecipitation-ultrasonication method. The reaction was carried out under a inert gas environment. The nanoparticles were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), fourier-transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry techniques (VSM), the surface area of the nanoparticles was determined to be 77.92 m2/g by Brunauer-Emmett-Teller method (BET). The kinetic data showed that the adsorption process fitted with the pseudo-second order model. Batch experiments were carried out to determine the adsorption kinetics and mechanisms of Cr(VI) by Fe3O4/Talc nanocomposite. The adsorption process was found to be highly pH-dependent, which made the material selectively adsorb these metals from aqueous solution. The isotherms of adsorption were also studied using Langmuir and Freundlich equations in linear forms. It is found that the Langmuir equation showed better linear correlation with the experimental data than the Freundlich. The thermodynamics of Cr(VI) adsorption onto the Fe3O4/Talc nanocomposite indicated that the adsorption was exothermic. The reusability study has proven that Fe3O4/Talc nanocomposite can be employed as a low-cost and easy to separate.

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