scholarly journals Corrosion Behavior of Fe/Zr Composite Coating on ZK60 Mg Alloy by Ion Implantation and Deposition

Coatings ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 261 ◽  
Author(s):  
Yang Zheng ◽  
Libin Zang ◽  
Yanze Bi ◽  
Yan Li ◽  
Yong Chen

The Fe/Zr composite coating was prepared by duplex Fe/Zr ion implantation and deposition to modify the microstructure and corrosion behavior of Mg-5.5 Zn-0.6 Zr (in wt.%, ZK60) alloy. The surface and interface characteristics were investigated using X-ray diffraction (XRD), atomic force microscope (AFM) and scanning electron microscopy (SEM). The results showed that the Fe/Zr composite coating exhibited a bi-layer microstructure of outer Fe-rich layer and inner Zr-rich layer. Multi-phases of α-Fe, ZrO0.35 and Zr6Fe3O were formed on the modified surface. The electrochemical measurements and immersion tests revealed an improvement of corrosion behavior for the surface-modified sample due to the protective effect of Fe/Zr composite coating.

2012 ◽  
Vol 90 (1) ◽  
pp. 39-43 ◽  
Author(s):  
X. Xiang ◽  
D. Chang ◽  
Y. Jiang ◽  
C.M. Liu ◽  
X.T. Zu

Anatase TiO2 thin films are deposited on K9 glass samples at different substrate temperatures by radio frequency magnetron sputtering. N ion implantation is performed in the as-deposited TiO2 thin films at ion fluences of 5 × 1016, 1 × 1017, and 5 × 1017 ions/cm2. X-ray diffraction, atomic force microscope, X-ray photoelectron spectroscopy (XPS), and UV–visible spectrophotometer are used to characterize the films. With increasing N ion fluences, the absorption edges of anatase TiO2 films shift to longer wavelengths and the absorbance increases in the visible light region. XPS results show that the red shift of TiO2 films is due to the formation of N–Ti–O compounds. As a result, photoactivity is enhanced with increasing N ion fluence.


2012 ◽  
Vol 730-732 ◽  
pp. 257-262
Author(s):  
Bruno Nunes ◽  
Sergio Magalhães ◽  
Nuno Franco ◽  
Eduardo Alves ◽  
Ana Paula Serro ◽  
...  

Aiming to improve the nanotribological response of Si-based materials we implanted silicon wafers with different fluences of iron ions (up to 2x1017 cm-2). Implantation was followed by annealing treatments at temperatures from 550°C to 1000°C. The implanted surfaces were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), atomic force microscopy (AFM) and wettability tests. Then, samples were submitted to AFM-based nanowear tests. We observe an increase of both hidrophobicity and and wear resistance of the implanted silicon, indicating that ion implantation of Si can be a route to be deeper explored in what concerns tribomechanical improvement of Si.


Author(s):  
Hina Javed ◽  
Kalsoom Fatima ◽  
Zareen Akhter ◽  
Muhammad Arif Nadeem ◽  
Muhammad Siddiq ◽  
...  

We have investigated the attachment of azobenzene photochromic switches on the modified surface of cadmium sulfide (CdS) quantum dots (QDs). The modification of CdS QDs is done by varying the concentration of the capping agent (mercaptoacetic acid) and NH 3 in order to control the size of the QDs. The X-ray diffraction studies revealed that the crystallite size of CdS QDs ranged from 6 to 10 nm. The azobenzene photochromic derivatives bis(4-hydroxybenzene-1-azo)4,4′(1,1′ diphenylmethane) (I) and 4,4′-diazenyldibenzoic acid (II) were synthesized and attached with surface-modified CdS QDs to make fluorophore–photochrome CdS-(I) and CdS-(II) dyad assemblies. Upon UV irradiation, the photochromic compounds (I) and (II) undergo a reversible trans – cis isomerization. The photo-induced trans – cis transformation helps to transfer photo-excited electrons from the conduction band of the CdS QDs to the lowest unoccupied molecular orbital of cis isomer of photochromic compounds (I) and (II). As a result, the fluorescence of CdS-(I) and CdS-(II) dyads is suppressed approximately five times compared to bare CdS QDs. The fluorescence modulation in such systems could help to design luminescent probes for bioimaging applications.


Author(s):  
Jie Teng ◽  
Zili Xu ◽  
Jinlong Su ◽  
Yuan Li

Abstract In this study, hydroxyapatite-reinforced ZK60 Mg alloybased composites were fabricated via a powder metallurgy route. The mechanical properties of these composites were studied by compressive tests and hardness tests. The in-vitro corrosion behavior was also investigated using immersion testing and electrochemical measurement. The influence of hydroxyapatite content on the mechanical properties and invitro corrosion behavior was evaluated. The microstructure and corrosion morphology were characterized by means of X-ray diffraction, optical and scanning electron microscopy. The results showed that the composite materials with 10 wt.% hydroxyapatite exhibited a better combination of mechanical strength and corrosion resistance. Compared with ZK60 alloy, the addition of 10 wt.% hydroxyapatite resulted in an increase in corrosion resistance by 38.6%.


2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Meiyan Li ◽  
Bin Han ◽  
Conghua Qi ◽  
Yong Wang ◽  
Lixin Song

The composite processing between laser cladding and low temperature (300°C) ion sulfurization was applied to prepare wear resistant and self-lubricating coating. The microstructure, morphology, phase composition, valence states, and wear resistance of the composite coating were investigated by scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS), and friction and wear apparatus. The results indicate that the laser cladding Ni-based coatings and the maximum hardness of 46.5 HRC were obtained when the percent of pure W powder was 10%, composed of columnar dendrites crystals and ultrafine dendritic structure. After ion sulfurization at 300°C for 4 h, the loose and porous composite coating is formed with nanograins and the granularity of all grains is less than 100 nm, which consists ofγ-(Fe, Ni), M23C6carbides, FeS, FeS2, and WS2. Furthermore, the wear resistance of the composite coating is better than the laser cladding Ni55 + 10%W coating, and the friction coefficient and mass losses under the conditions of dry and oil lubrication are lower than those of laser cladding Ni55 + 10%W coating.


2002 ◽  
Vol 16 (23) ◽  
pp. 3439-3447 ◽  
Author(s):  
X. M. CHEN ◽  
Y. WANG ◽  
C. X. LIU ◽  
Y. N. ZHAO ◽  
Z. H. MAI ◽  
...  

La 0.5 Ca 0.5 MnO 3 (LCMO) thin films grown on SrTiO 3 substrate with different thickness were investigated using high resolution X-ray diffraction, small angle reflectivity, and atomic force microscope (AFM). All the films are demonstrated to be c-axis oriented. The surface and interface structure of the films were obtained. It was found that the surface morphology of the films strongly depends on the thickness, and the film will crack when the thickness of the film reach a critical thickness. The surface roughness of the films increases with the thickness. The interface between the films and the substrates are very clear. There exists a non-designed cap layer on the surface of the LCMO layer.


2007 ◽  
Vol 361-363 ◽  
pp. 673-676
Author(s):  
E.T. Uzumaki ◽  
C.S. Lambert

Plasma immersion ion implantation (PIII) is a very attractive method for the surface treatment of titanium hard tissue replacements such as hip joints and enhancement of the mechanical, chemical and biological properties of titanium. It has been considered as an alternative to form protective and hard oxide films on titanium and titanium-based implants. In this study, titanium oxide (TiO2) thin films were formed on titanium using PIII, which produces films with adhesion superior to those prepared with conventional techniques. The films were analysed by atomic force microscopy (AFM), X-ray diffraction (XRD) and pull test.


1996 ◽  
Vol 156 (1-3) ◽  
pp. 109-110 ◽  
Author(s):  
K. Temst ◽  
M.J. Van Bael ◽  
D.G. de Groot ◽  
N.J. Koeman ◽  
R.P. Griessen ◽  
...  

Coatings ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 931 ◽  
Author(s):  
Zhipo Zhao ◽  
Junrong Tang ◽  
Naeem ul Haq Tariq ◽  
Jiqiang Wang ◽  
Xinyu Cui ◽  
...  

A Zn–Al composite coating was successfully deposited on Q235 steel by cold spray technology for the corrosion protection in the marine atmosphere. The microstructure and corrosion behavior of the prepared coating was studied byScanning Electron Microscope (SEM), X-ray Diffraction (XRD), salt spray test and electrochemical experiments. A 2400-h neutral salt spray corrosion test (with a corrosion medium of 3.5% sodium chloride solution) showed that the prepared cold-sprayed Zn-Al composite coating has excellent anti-corrosion properties. Based on the microstructure evolution and corrosion products analysis, droplets’ flow-driven ‘synergistic corrosion effect’ was proposed to explain the co-corrosion behavior of Zn and Al particles in the composite coating.


2013 ◽  
Vol 372 ◽  
pp. 75-79
Author(s):  
Haiou Wang ◽  
Hao Liu ◽  
Meng Xiong Cao ◽  
Wei Shi Tan ◽  
Ping Dai ◽  
...  

Epitaxial bilayer structure consisting of ferromagnetic (FM) metallic Pr0.7Sr0.3MnO3 (PSMO) and antiferromagnetic (AFM) insulator La0.5Ca0.5MnO3 (LCMO) was fabricated on (001)-oriented single crystal SrTiO3 (STO) substrate by pulsed laser deposition technique. We studied the surface structure and interdiffusion at interface between PSMO and LCMO by using atomic force microscope and grazing incident x-ray reflectivity (GIXRR). The perfect data fitting result of GIXRR indicated that interdiffusion at the interface of Pr0.7Sr0.3MnO3/La0.5Ca0.5MnO3 (PSMO/LCMO) could not be negligible; there was a large interdiffusion zone at the PSMO/LCMO interfaces with a thickness of about 7 nm. We found that the thickness of the top layer at air/PSMO interface was about 2.5 nm and the mass density of the top layer was about 76.53% of that of PSMO layer. The surface roughness was about 1.6 nm which was consistent with observation by atomic force microscopy. Normal X-ray diffraction (NXRD) was also employed to investigate the average structure. Except from PSMO and LCMO layer diffraction peaks, we observed another additional peak, which was developed from the large disordered layer resulting from interdiffusion at the interface of PSMO/LCMO. This implied that the variation of crystalline structure of PSMO/LCMO film occurred due to interdiffusion. Surface roughness and interdiffusion played an important role in magnetic properties of FM/AFM bilayer.


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