Corrosion Resistance Dependence of Rare Earth NiCrMoY Alloy Coatings

2014 ◽  
Vol 665 ◽  
pp. 107-110 ◽  
Author(s):  
Chun Lian Hu

The wear and corrosion of rare earth NiCrMoY alloy manufactured by atomization and oxygen-acetylene flame spray and high frequency induction remelting technique are investigated by a combination of scanning electron microscopy (SEM), energy spectrum, X-ray diffraction meter (XRD), uniform corrosion method of laboratory immersion test, anodic polarization curve of three electrodes potentiodynamic scan. The results indicate that Corrosion rate of NiCrMoY alloy coatings is better than that of Ni60A coatings in HCl, H2SO4, HNO3 and artificial seawater, and its wear is much better than those of Ni60A coatings.

2014 ◽  
Vol 577 ◽  
pp. 62-65
Author(s):  
Chun Lian Hu ◽  
Shang Lin Hou

The microstructure of rare earth NiCrMoY alloy manufactured by atomization and oxygen-acetylene flame spray and high frequency induction remelting technique is investigated by a combination of scanning electron microscopy (SEM), energy spectrum, X-ray diffraction meter (XRD). The results indicate that Microstructure of NiCrMoY alloy coatings are finer and bulk-and needle-like hard Metallograph are precipitated, a new phase MoB is produced.


Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 724
Author(s):  
Sara Massardo ◽  
Alessandro Cingolani ◽  
Cristina Artini

Rare earth-doped ceria thin films are currently thoroughly studied to be used in miniaturized solid oxide cells, memristive devices and gas sensors. The employment in such different application fields derives from the most remarkable property of this material, namely ionic conductivity, occurring through the mobility of oxygen ions above a certain threshold temperature. This feature is in turn limited by the association of defects, which hinders the movement of ions through the lattice. In addition to these issues, ionic conductivity in thin films is dominated by the presence of the film/substrate interface, where a strain can arise as a consequence of lattice mismatch. A tensile strain, in particular, when not released through the occurrence of dislocations, enhances ionic conduction through the reduction of activation energy. Within this complex framework, high pressure X-ray diffraction investigations performed on the bulk material are of great help in estimating the bulk modulus of the material, and hence its compressibility, namely its tolerance toward the application of a compressive/tensile stress. In this review, an overview is given about the correlation between structure and transport properties in rare earth-doped ceria films, and the role of high pressure X-ray diffraction studies in the selection of the most proper compositions for the design of thin films.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Michael Zoller ◽  
Hubert Huppertz

AbstractThe rare earth oxoborates REB5O8(OH)2 (RE = Ho, Er, Tm) were synthesized in a Walker-type multianvil apparatus at a pressure of 2.5 GPa and a temperature of 673 K. Single-crystal X-ray diffraction data provided the basis for the structure solution and refinement. The compounds crystallize in the monoclinic space group C2 (no. 5) and are composed of a layer-like structure containing dreier and sechser rings of corner sharing [BO4]5− tetrahedra. The rare earth metal cations are coordinated between two adjacent sechser rings. Further characterization was performed utilizing IR spectroscopy.


Author(s):  
Simon Engelbert ◽  
Rolf-Dieter Hoffmann ◽  
Jutta Kösters ◽  
Steffen Klenner ◽  
Rainer Pöttgen

Abstract The structures of the equiatomic stannides RERhSn with the smaller rare earth elements Y, Gd-Tm and Lu were reinvestigated on the basis of temperature-dependent single crystal X-ray diffraction data. GdRhSn crystallizes with the aristotype ZrNiAl at 293 and 90 K. For RE = Y, Tb, Ho and Er the HP-CeRuSn type (approximant with space group R3m) is already formed at room temperature, while DyRhSn adopts the HP-CeRuSn type below 280 K. TmRhSn and LuRhSn show incommensurate modulated variants with superspace groups P31m(1/3; 1/3; γ) 000 (No. 157.1.23.1) (γ = 3/8 for TmRhSn and γ = 2/5 for LuRhSn). The driving force for superstructure formation (modulation) is a strengthening of Rh–Sn bonding. The modulation is expressed in a 119Sn Mössbauer spectrum of DyRhSn at 78 K through line broadening.


2012 ◽  
Vol 525-526 ◽  
pp. 277-280
Author(s):  
Guo Jin ◽  
Xiu Fang Cui ◽  
Er Bao Liu ◽  
Qing Fen Li

The effect of the neodymium content on mechanical properties of the electro-brush plated nanoAl2O3/Ni composite coating was investigated in this paper. The microstructure and phase structure were studied with scanning electron microscope (SEM) and X-ray diffraction (XRD). The hardness and abrasion properties of several coatings with different neodymium content were studied by nanoindentation test and friction / wear experiment. Results show that the coatings are much finer and more compact when the neodymium was added, and the hardness and abrasion property of the coatings with neodymium were improved obviously. Besides, the small cracks conduced by the upgrowth stress in the coatings were ameliorated when the rare earth neodymium was added. The improvement mechanism was further discussed.


2011 ◽  
Vol 299-300 ◽  
pp. 77-81
Author(s):  
Yang Xu ◽  
Sheng Zhi Hao ◽  
Xiang Dong Zhang ◽  
Min Cai Li ◽  
Chuang Dong

The surface irradiation of 6063 aluminum alloy by high current pulsed electron was conducted with the aim of replacing the complicated pre-treatment in the processes of electroless plating. To explore the microstructure changes, optical metallography, SEM (scanning electron microscope), XRD (X-ray diffraction) analyses were carried out, and the sliding tests were used for the detection of wear resistance. It was concluded that the HCPEB irradiation could replace the pre-treatment of aluminum substrate as required in conventional electroless plating with a decreased surface roughness of Ni-P alloy plating layer. The plates exhibited an amorphous microstructure as demonstrated by XRD analysis. The plates, produced with the routine of HCPEB irradiation, activation and electroless plating possess, also exhibited good quality, even better than that of conventional electroless plating technique.


1989 ◽  
Vol 151 ◽  
Author(s):  
W. R. Bennett ◽  
R. F. C. Farrow ◽  
S. S. P. Parkin ◽  
E. E. Marinero

ABSTRACTWe report on the new epitaxial system LaF3/Er/Dy/Er/LaF3/GaAs (111) grown by molecular beam epitaxy. X-ray diffraction studies have been used to determine the epitaxial relationships between the rare earths, the LaF3 and the substrate. Further studies of symmetric and asymmetric reflections yielded the in-plane and perpendicular strain components of the rare earth layers. Such systems may be used to probe the effects of magnetoelastic interactions and dimensionality on magnetic ordering in rare earth metal films and multilayers.


Author(s):  
Laura A. Lallemand ◽  
James G. McCarthy ◽  
Sean McSweeney ◽  
Andrew A. McCarthy

Chlorogenic acids (CGAs) are a group of soluble phenolic compounds that are produced by a variety of plants, includingCoffea canephora(robusta coffee). The last step in CGA biosynthesis is generally catalysed by a specific hydroxycinnamoyl-CoA quinate hydroxycinnamoyltransferase (HQT), but it can also be catalysed by the more widely distributed hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyltransferase (HCT). Here, the cloning and overexpression of HCT fromC. canephorainEscherichia colias well as its purification and crystallization are presented. Crystals were obtained by the sitting-drop technique at 293 K and X-ray diffraction data were collected on the microfocus beamline ID23-2 at the ESRF. The HCT crystals diffracted to better than 3.0 Å resolution, belonged to space groupP42212 with unit-cell parametersa=b= 116.1,c= 158.9 Å and contained two molecules in the asymmetric unit. The structure was solved by molecular replacement and is currently under refinement. Such structural data are needed to decipher the molecular basis of the substrate specifities of this key enzyme, which belongs to the large plant acyl-CoA-dependent BAHD acyltransferase superfamily.


2018 ◽  
Vol 82 (2) ◽  
pp. 313-327
Author(s):  
Markus B. Raschke ◽  
Evan J. D. Anderson ◽  
Jason Van Fosson ◽  
Julien M. Allaz ◽  
Joseph R. Smyth ◽  
...  

ABSTRACTThalénite-(Y), ideally Y3Si3O10F, is a heavy-rare-earth-rich silicate phase occurring in granite pegmatites that may help to illustrate rare-earth element (REE) chemistry and behaviour in natural systems. The crystal structure and mineral chemistry of thalénite-(Y) were analysed by electron microprobe analysis, X-ray diffraction and micro-Raman spectroscopy from a new locality in the peralkaline granite of the Golden Horn batholith, Okanogan County, Washington State, USA, in comparison with new analyses from the White Cloud pegmatite in the Pikes Peak batholith, Colorado, USA. The Golden Horn thalénite-(Y) occurs as late-stage sub-millimetre euhedral bladed transparent crystals in small miarolitic cavities in an arfvedsonite-bearing biotite granite. It exhibits growth zoning with distinct heavy-rare-earth element (HREE) vs. light-rare-earth element (LREE) enriched zones. The White Cloud thalénite-(Y) occurs in two distinct anhedral and botryoidal crystal habits of mostly homogenous composition. In addition, minor secondary thalénite-(Y) is recognized by its distinct Yb-rich composition (up to 0.8 atoms per formula unit (apfu) Yb). Single-crystal X-ray diffraction analysis and structure refinement reveals Y-site ordering with preferential HREE occupation of Y2 vs. Y1 and Y3 REE sites. Chondrite normalization shows continuous enrichment of HREE in White Cloud thalénite-(Y), in contrast to Golden Horn thalénite-(Y) with a slight depletion of the heaviest REE (Tm, Yb and Lu). The results suggest a hydrothermal origin of the Golden Horn miarolitic thalénite-(Y), compared to a combination of both primary magmatic followed by hydrothermal processes responsible for the multiple generations over a range of spatial scales in White Cloud thalénite-(Y).


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