Explosive Welding of Thin Aluminum Plate onto Magnesium Alloy Plate Using a Gelatin Layer as a Pressure-Transmitting Medium

Mg alloys are extensively used in various automotive, aerospace, and industrial applications. Their limited corrosion resistance can be enhanced by welding a thin Al plate onto the alloy surface. In this study, we perform the explosive welding of a thin Al plate, accelerated by the detonation of an explosive through a gelatin layer as a pressure-transmitting medium, onto two Mg alloy samples: Mg96Zn2Y2 alloy containing a long-period stacking ordered phase in an α-Mg matrix and commercial AZ31. The bonding interface is characterized using optical microscopy, scanning electron microscopy, X-ray diffraction, and electron probe microanalysis. Under moderate experimental conditions, the thin Al plates are successfully welded onto the Mg alloys, showing typical wavy interfaces without intermediate layers. Due to the decreased energetic condition corresponding to the use of a thin flyer plate and gelatin medium, the resulting bonding quality is better than that obtained using a regular explosive welding technique. Further, based on the well-known window for explosive welding, we estimate that the experimental conditions for successful bonding are close to the lower welding limit for a thin Al plate with the two Mg alloys considered. These findings may contribute to improving the quality of materials welded with explosive welding.

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Adjustment of the Mechanical Properties of Mg2Nd and Mg2Yb by Optimizing Their Microstructures

Metals ◽

10.3390/met11030377 ◽

2021 ◽

Vol 11 (3) ◽

pp. 377

Author(s):

Jonas Schmidt ◽

Irene J. Beyerlein ◽

Marko Knezevic ◽

Walter Reimers

Keyword(s):

Tensile Tests ◽

Industrial Applications ◽

Heat Treatments ◽

Mg Alloys ◽

Mechanical Anisotropy ◽

Compression Tests ◽

X Ray Diffraction ◽

Active Deformation ◽

Strength Differential ◽

Wide Range

The deformation behavior of the extruded magnesium alloys Mg2Nd and Mg2Yb was investigated at room temperature. By using in situ energy-dispersive synchrotron X-ray diffraction compression and tensile tests, accompanied by Elasto-Plastic Self-Consistent (EPSC) modeling, the differences in the active deformation systems were analyzed. Both alloying elements change and weaken the extrusion texture and form precipitates during extrusion and subsequent heat treatments relative to common Mg alloys. By varying the extrusion parameters and subsequent heat treatment, the strengths and ductility can be adjusted over a wide range while still maintaining a strength differential effect (SDE) of close to zero. Remarkably, the compressive and tensile yield strengths are similar and there is no mechanical anisotropy when comparing tensile and compressive deformation, which is desirable for industrial applications. Uncommon for Mg alloys, Mg2Nd shows a low tensile twinning activity during compression tests. We show that heat treatments promote the nucleation and growth of precipitates and increase the yield strengths isotopically up to 200 MPa. The anisotropy of the yield strength is reduced to a minimum and elongations to failure of about 0.2 are still achieved. At lower strengths, elongations to failure of up to 0.41 are reached. In the Mg2Yb alloy, adjusting the extrusion parameters enhances the rare-earth texture and reduces the grain size. Excessive deformation twinning is, however, observed, but despite this the SDE is still minimized.

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A Review on LDH-Smart Functionalization of Anodic Films of Mg Alloys

Nanomaterials ◽

10.3390/nano11020536 ◽

2021 ◽

Vol 11 (2) ◽

pp. 536

Author(s):

Mosab Kaseem ◽

Karna Ramachandraiah ◽

Shakhawat Hossain ◽

Burak Dikici

Keyword(s):

Industrial Applications ◽

Mg Alloys ◽

Anodic Films ◽

Electrolytic Oxidation ◽

Recent Developments ◽

Plasma Electrolytic ◽

Co Precipitation ◽

Corrosive Environments ◽

Double Hydroxide

This review presents an overview of the recent developments in the synthesis of layered double hydroxide (LDH) on the anodized films of Mg alloys prepared by either conventional anodizing or plasma electrolytic oxidation (PEO) and the applications of the formed composite ceramics as smart chloride traps in corrosive environments. In this work, the main fabrication approaches including co-precipitation, in situ hydrothermal, and an anion exchange reaction are outlined. The unique structure of LDH nanocontainers enables them to intercalate several corrosion inhibitors and release them when required under the action of corrosion-relevant triggers. The influences of different variables, such as type of cations, the concentration of salts, pH, and temperature, immersion time during the formation of LDH/anodic film composites, on the electrochemical response are also highlighted. The correlation between the dissolution rate of PEO coating and the growth rate of the LDH film was discussed. The challenges and future development strategies of LDH/anodic films are also highlighted in terms of industrial applications of these materials.

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Zeolite NaP1 Functionalization for the Sorption of Metal Complexes with Biodegradable N-(1,2-dicarboxyethyl)-D,L-aspartic Acid

Materials ◽

10.3390/ma14102518 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2518

Author(s):

Dorota Kołodyńska ◽

Yongming Ju ◽

Małgorzata Franus ◽

Wojciech Franus

Keyword(s):

Experimental Data ◽

Aspartic Acid ◽

Ph Value ◽

Complexing Agents ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Modified Zeolite ◽

X Ray ◽

Slow Release Fertilizers ◽

Pseudo Second Order

The possibility of application of chitosan-modified zeolite as sorbent for Cu(II), Zn(II), Mn(II), and Fe(III) ions and their mixtures in the presence of N-(1,2-dicarboxyethyl)-D,L-aspartic acid, IDHA) under different experimental conditions were investigated. Chitosan-modified zeolite belongs to the group of biodegradable complexing agents used in fertilizer production. NaP1CS as a carrier forms a barrier to the spontaneous release of the fertilizer into soil. The obtained materials were characterized by Fourier transform infrared spectroscopy (FTIR); surface area determination (ASAP); scanning electron microscopy (SEM-EDS); X-ray fluorescence (XRF); X-ray diffraction (XRD); and carbon, hydrogen, and nitrogen (CHN), as well as thermogravimetric (TGA) methods. The concentrations of Cu(II), Zn(II), Mn(II), and Fe(III) complexes with IDHA varied from 5–20 mg/dm3 for Cu(II), 10–40 mg/dm3 for Fe(III), 20–80 mg/dm3 for Mn(II), and 10–40 mg/dm3 for Zn(II), respectively; pH value (3–6), time (1–120 min), and temperature (293–333 K) on the sorption efficiency were tested. The Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin adsorption models were applied to describe experimental data. The pH 5 proved to be appropriate for adsorption. The pseudo-second order and Langmuir models were consistent with the experimental data. The thermodynamic parameters indicate that adsorption is spontaneous and endothermic. The highest desorption percentage was achieved using the HCl solution, therefore, proving that method can be used to design slow-release fertilizers.

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Selective growth of Ti3+/TiO2/CNT and Ti3+/TiO2/C nanocomposite for enhanced visible-light utilization to degrade organic pollutants by lowering TiO2-bandgap

Scientific Reports ◽

10.1038/s41598-021-89026-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jeasmin Akter ◽

Md. Abu Hanif ◽

Md. Akherul Islam ◽

Kamal Prasad Sapkota ◽

Jae Ryang Hahn

Keyword(s):

Visible Light ◽

Structural Integrity ◽

Carbon Layer ◽

Wide Bandgap ◽

Blue Dye ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Excellent Photocatalytic Activity ◽

Convenient Route ◽

Walled Carbon Nanotubes

AbstractA convenient route was developed for the selective preparation of two stable nanocomposites, Ti3+/TiO2/CNT (labeled as TTOC-1 and TTOC-3) and Ti3+/TiO2/carbon layer (labeled as TTOC-2), from the same precursor by varying the amount of single-walled carbon nanotubes used in the synthesis. TiO2 is an effective photocatalyst; however, its wide bandgap limits its usefulness to the UV region. As a solution to this problem, our prepared nanocomposites exhibit a small bandgap and wide visible-light (VL) absorption because of the introduction of carbonaceous species and Ti3+ vacancies. The photocatalytic efficiency of the nanocomposites was examined via the degradation of methylene blue dye under VL. Excellent photocatalytic activity of 83%, 98%, and 93% was observed for TTOC-1, TTOC-2, and TTOC-3 nanocomposites within 25 min. In addition, the photocatalytic degradation efficiency of TTOC-2 toward methyl orange, phenol, rhodamine B, and congo red was 28%, 69%, 71%, and 91%, respectively, under similar experimental conditions after 25 min. Higher reusability and structural integrity of the as-synthesized photocatalyst were confirmed within five consecutive runs by photocatalytic test and X-ray diffraction analysis, respectively. The resulting nanocomposites provide new insights into the development of VL-active and stable photocatalysts with high efficiencies.

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Statistical analysis of the reproducibility of residual stress measurements in cold extruded parts

Archive of Applied Mechanics ◽

10.1007/s00419-021-01953-x ◽

2021 ◽

Author(s):

Fabian Jaeger ◽

Alessandro Franceschi ◽

Holger Hoche ◽

Peter Groche ◽

Matthias Oechsner

Keyword(s):

Residual Stress ◽

Statistical Analysis ◽

Stress Measurement ◽

Industrial Applications ◽

Cold Extrusion ◽

X Ray Diffraction ◽

Forming Process ◽

X Ray ◽

Stress States ◽

Key Aspects

AbstractCold extruded components are characterized by residual stresses, which originate from the experienced manufacturing process. For industrial applications, reproducibility and homogeneity of the final components are key aspects for an optimized quality control. Although striving to obtain identical deformation and surface conditions, fluctuation in the manufacturing parameters and contact shear conditions during the forming process may lead to variations of the spatial residual stress distribution in the final product. This could lead to a dependency of the residual stress measurement results on the relative axial and circumferential position on the sample. An attempt to examine this problem is made by the employment of design of experiments (DoE) methods. A statistical analysis of the residual stress results generated through X-Ray diffraction is performed. Additionally, the ability of cold extrusion processes to generate uniform stress states is analyzed on specimens of austenitic stainless steel 1.4404 and possible correlations with the pre-deformed condition are statistically examined. Moreover, the influence of the coating, consisting of oxalate and a MoS2 based lubricant, on the X-Ray diffraction measurements of the surface is investigated.

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Discovery of Fe7O9: a new iron oxide with a complex monoclinic structure

Scientific Reports ◽

10.1038/srep32852 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 20

Author(s):

Ryosuke Sinmyo ◽

Elena Bykova ◽

Sergey V. Ovsyannikov ◽

Catherine McCammon ◽

Ilya Kupenko ◽

...

Keyword(s):

Applied Sciences ◽

Crystal Structure ◽

Iron Oxide ◽

Iron Oxides ◽

Industrial Applications ◽

Ambient Conditions ◽

X Ray Diffraction ◽

X Ray ◽

High Pressure High Temperature ◽

Insight Into

Abstract Iron oxides are fundamentally important compounds for basic and applied sciences as well as in numerous industrial applications. In this work we report the synthesis and investigation of a new binary iron oxide with the hitherto unknown stoichiometry of Fe7O9. This new oxide was synthesized at high-pressure high-temperature (HP-HT) conditions, and its black single crystals were successfully recovered at ambient conditions. By means of single crystal X-ray diffraction we determined that Fe7O9 adopts a monoclinic C2/m lattice with the most distorted crystal structure among the binary iron oxides known to date. The synthesis of Fe7O9 opens a new portal to exotic iron-rich (M,Fe)7O9 oxides with unusual stoichiometry and distorted crystal structures. Moreover, the crystal structure and phase relations of such new iron oxide groups may provide new insight into the cycling of volatiles in the Earth’s interior.

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Dispersion of TiO2 Nanotubes in a Chitosan Matrix

MRS Advances ◽

10.1557/adv.2018.598 ◽

2018 ◽

Vol 3 (63) ◽

pp. 3805-3810

Author(s):

B. Núñez Mendoza ◽

S.R. Vasquez-García ◽

N. Flores-Ramírez ◽

J. L. Rico ◽

L. Zamora Peredo ◽

...

Keyword(s):

Electrochemical Anodization ◽

Infrared Spectrometry ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Second Stage ◽

Chitosan Matrix ◽

Third Stage ◽

Membrane Type ◽

Titanium Foils

ABSTRACTThis work presents the synthesis and characterization of TiO2 nanotubes (NTT) with chitosan (CS). In a first stage, electrochemical anodization of titanium foils was used to generate NTT in a membrane-type arrangement. From these experiments, suitable experimental conditions were selected. In a second stage, the synthesized NTT were detached from the titanium foils by sonication. In the third stage, the detached NTT were dispersed in an acid solution containing CS in various concentrations. Finally, the nanotubes-chitosan (NTT/CS) samples were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Fourier Transform Infrared Spectrometry (FTIR). Our results showed that the NTT presented very regular tube morphology with -OH and Ti-O- functional groups on the surface. The interaction of NTT and chitosan was enhanced by increasing the time of contact during the synthesis of the titanium composites.

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Bentonite Clays Characterization in the Town of Sossego – Paraiba State

Materials Science Forum ◽

10.4028/www.scientific.net/msf.820.65 ◽

2015 ◽

Vol 820 ◽

pp. 65-70

Author(s):

I.D.S. Pereira ◽

V.N.F. Lisboa ◽

I.A. Silva ◽

J.M.R. Figueirêdo ◽

G.A. Neves ◽

...

Keyword(s):

Industrial Applications ◽

Particle Size Analysis ◽

Size Analysis ◽

Drilling Fluids ◽

X Ray Diffraction ◽

Mineralogical Characterization ◽

Bentonite Clays ◽

The Town ◽

Petroleum Drilling

Bentonite exhibt a range of industrial applications moving millions of dollars on the market per year. Among several applications if highlights it is use for petroleum drilling fluids. Thus, this work aims to characterize physical, mineralogical and technologically, the bentonitics clays of Sossego County, Paraíba, Brazil. Mineralogical characterization of clays was done through the following techniques: particle size analysis by laser diffraction, thermogravimetric and differential thermal analysis, chemical analysis and x-ray diffraction. The clays were turned in by treatment with sodium in Na2CO3 and then determined whether the apparent viscosity, plastic and volume of filtrate of clay-water dispersions. The results showed that the samples are of polycationic, showing levels of MgO, CaO and K2O, similar to those from Boa Vista County, Paraíba, Brazil, and consist of clay mineral kaolinite, quartz and esmec. The clays showed rheological properties that indicate potential for use in drilling fluids.

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Formation of Pharmaceutical Salts and Cocrystals via Vapour-Assisted Tumbling (VAT) – A Solvent Efficient Process with Potential Industrial Applications

10.33774/chemrxiv-2021-qgnfh-v2 ◽

2021 ◽

Author(s):

Alexander J. Stirk ◽

Fabio E. S. Souza ◽

Jenny Gerster ◽

Fatemeh M. Mir ◽

Avedis Karadeolian ◽

...

Keyword(s):

Differential Scanning Calorimetry ◽

Environmental Impact ◽

Industrial Applications ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

New Techniques ◽

X Ray ◽

Industry Standard ◽

Pharmaceutical Salts ◽

Solid Form

Crystallisations on both the academic and industrial scale often use large volumes of solvent. In order decrease the environmental impact of such processes, new techniques must be discovered that increase the efficiency of the solvents used. Introduced here is a process that combines repurposed industry standard hardware and aspects of mechanochemistry to produce a technique we call “Vapour Assisted Tumbling” (VAT). Pharmaceutical and well-known cocrystals and salts were formed by tumbling the coformers in an atmosphere of vaporised solvent, in this study, methanol (MeOH). This was done inside a custom built analogue of an industrial rotary cone dryer (RCD). It was found that a desired solid form could be obtained as monitored by powder X-ray diffraction and differential scanning calorimetry. By repurposing industrial RCDs, it is feasible that solid forms can be crystallised with both minimal and reusable/recyclable solvent – drastically lowering the environmental impact of such transformations.

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Theoretical study of the properties of X-ray diffraction moiré fringes. II. Illustration of angularly integrated moiré images

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273319004601 ◽

2019 ◽

Vol 75 (4) ◽

pp. 610-623

Author(s):

Jun-ichi Yoshimura

Keyword(s):

Incident Wave ◽

Angular Width ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Acta Cryst ◽

Low Contrast ◽

X Ray ◽

Moiré Fringes ◽

Wide Range ◽

Fringe Patterns

Using a theory of X-ray diffraction moiré fringes developed in a previous paper, labelled Part I [Yoshimura (2015). Acta Cryst. A71, 368–381], the X-ray moiré images of a silicon bicrystal having a weak curvature strain and an interspacing gap, assumed to be integrated for an incident-wave angular width, are simulation-computed over a wide range of crystal thicknesses and incident-wave angular width, likely under practical experimental conditions. Along with the simulated moiré images, the graphs of characteristic quantities on the moiré images are presented for a full understanding of them. The treated moiré images are all of rotation moiré. Mo Kα1 radiation and the 220 reflection were assumed in the simulation. The results of this simulation show that fringe patterns, which are significantly modified from simple straight fringes of rotation moiré, appear in some ranges of crystal thicknesses and incident-wave angular width, due to a combined effect of Pendellösung oscillation and an added phase difference from the interspacing gap, under the presence of a curvature strain. The moiré fringes which slope to the perpendicular direction to the diffraction vector in spite of the assumed condition of rotation moiré, and fringe patterns where low-contrast bands are produced with a sharp bend of fringes arising along the bands are examples of the modified fringe pattern. This simulation study provides a wide theoretical survey of the type of bicrystal moiré image produced under a particular condition.

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