Study on Salt Fog Corrosion of FeCoCrMoCBY Amorphous/Nanocrystalline Alloy Coating

Fe-based amorphous alloy coating with a composition of Fe41Co7Cr15Mo14C15B6Y2was prepared by high velocity fuel(HVOF) technique. The influence of heat treatment on crystalline behavior, the phase structure and corroded morphology of the coating was investigated by Differential Thermal Analysis(DTA), X-ray Diffraction (XRD), Scanning Electron Microscopy(SEM), respectively. The experimental results indicate that the amorphous alloy coating exhibited a two-step crystallization process with crystallization peak temperature at 698°C and 822°C, respectively. Amorphous coating exhibits excellent corrosion resistance than that of the corresponding nano-crystalline coating with heat treatment at 700°C for 2h, 8h and 12h. Furthermore, the nano-crystalline coating annealed 700°C for 12h suffers slight homogeneity corrosion, which did not exhibit obvious pitting on comparison with coating holding 2h and 8h.

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Synchrotron Nano-Diffraction Study of Thermally Treated Asbestos Tremolite from Val d’Ala, Turin (Italy)

Minerals ◽

10.3390/min8080311 ◽

2018 ◽

Vol 8 (8) ◽

pp. 311 ◽

Cited By ~ 2

Author(s):

Carlotta Giacobbe ◽

Jonathan Wright ◽

Dario Di Giuseppe ◽

Alessandro Zoboli ◽

Mauro Zapparoli ◽

...

Keyword(s):

Crystal Structure ◽

Heat Treatment ◽

Risk Management ◽

Structure Analysis ◽

X Rays ◽

X Ray Diffraction ◽

X Ray ◽

Adverse Health Effects ◽

Nano Crystalline ◽

Original Fibre

Nowadays, due to the adverse health effects associated with exposure to asbestos, its removal and thermal inertization has become one of the most promising ways for reducing waste risk management. Despite all the advances in structure analysis of fibers and characterization, some problems still remain that are very hard to solve. One challenge is the structure analysis of natural micro- and nano-crystalline samples, which do not form crystals large enough for single-crystal X-ray diffraction (SC-XRD), and their analysis is often hampered by reflection overlap and the coexistence of multiple fibres linked together. In this paper, we have used nano-focused synchrotron X-rays to refine the crystal structure of a micrometric tremolite fibres from Val d’Ala, Turin (Italy) after various heat treatment. The structure of the original fibre and after heating to 800 °C show minor differences, while the fibre that was heated at 1000 °C is recrystallized into pyroxene phases and cristobalite.

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In situ X-ray diffraction study of crystallization process of GeSbTe thin films during heat treatment

Applied Surface Science ◽

10.1016/j.apsusc.2004.10.145 ◽

2005 ◽

Vol 244 (1-4) ◽

pp. 281-284 ◽

Cited By ~ 28

Author(s):

Naohiko Kato ◽

Ichiro Konomi ◽

Yoshiki Seno ◽

Tomoyoshi Motohiro

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Diffraction Study ◽

Crystallization Process ◽

X Ray Diffraction ◽

X Ray

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Research on Properties of Amorphous Cr-C Alloy Coating in Crystallization Evolution

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.184-185.1175 ◽

2012 ◽

Vol 184-185 ◽

pp. 1175-1180

Author(s):

Guo Liang Li ◽

Xiao Hua Jie ◽

Bi Xue Yang

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Intermetallic Compound ◽

Adhesion Force ◽

Alloy Coating ◽

Treatment Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Proper Values ◽

Peak Value

Amorphous Cr–C alloy coating was prepared by electrodepositing. The microhardness of the coating was tested after annealing from 100°C to 800°C and the crystallization evolution was studied by the analysis of X-ray diffraction (XRD) and differential scanning caborimetry (DSC). The results showed that the crystallization evolution of the coating began at 300°C and finished around 450°C, and intermetallic compound Cr7C3and Cr23C6appeared when heat treatment temperature reached around 600°C. The microhardness, corrosion resistance as well as the adhesion of the coating all increased first with the temperature and then dropped until it attained the proper values. The microhardness reached the maximum of 1610HV0.025at 600°C. While the corrosion resistance and the adhesion force attained the peak value at about 400°C.

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Investigation on Properties of Electroless Ni-P-W/Al2O3 Composite Coatings Deposited on Sintered NdFeB Permanent Magnet

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.397 ◽

2012 ◽

Vol 476-478 ◽

pp. 397-401 ◽

Cited By ~ 2

Author(s):

Dong Yang ◽

Xin Xin Lin ◽

Huan Ming Chen ◽

Ya Hong Gao ◽

Qiong Lv ◽

...

Keyword(s):

Corrosion Resistance ◽

Amorphous Alloy ◽

Permanent Magnet ◽

Composite Coatings ◽

Alloy Coating ◽

Linear Increase ◽

X Ray Diffraction ◽

Ndfeb Magnet ◽

Plating Method ◽

Ndfeb Permanent Magnet

The Ni-P-W/Al2O3composite coatings were deposited on the surface of sintered NdFeB permanent magnet by electroless plating method. The morphology and the phases of Ni-P-W/Al2O3composite coatings were investigated using scanning electron microscopy and X-ray diffraction respectively. The hardness and the corrosion resistance of the composite coatings were also tested. The results indicated that the composite coatings morphology appears closely nodules morphology, and the microhardness increases linearly with increasing incorporation of Al2O3ratio. Compared with NdFeB magnet and Ni-P-W amorphous alloy coating, the corrosion resistance of the composite coatings was superior to that of the NdFeB magnet and the amorphous alloy coating obviously. However, for the corrosion resistance of Ni-P-W/Al2O3composite coatings with different Al2O3concentration, there is not a linear increase with the Al2O3concentration increasing. The self-corrosion potential of Ni-P-W/Al2O3composite coatings reaches the highest value while increasing incorporation of Al2O3ratio up to 10 g/L.

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Transparent Oxyfluoride Glass-Ceramics Containing CaF2 Nano-Crystalline Phase

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1015 ◽

2012 ◽

Vol 512-515 ◽

pp. 1015-1018 ◽

Cited By ~ 2

Author(s):

Zhao Xia Hou ◽

Zhao Lu Xue ◽

Shao Hong Wang ◽

Xiao Dan Hu ◽

Hao Ran Lu ◽

...

Keyword(s):

Heat Treatment ◽

Crystalline Phase ◽

Tellurite Glass ◽

Glass Ceramics ◽

Xrd Analysis ◽

Glassy Matrix ◽

The Novel ◽

X Ray Diffraction ◽

Oxyfluoride Glass ◽

Nano Crystalline

Transparent oxyfluoride tellurite glass with the composition of TeO2-SiO2-AlF3-CaO-KF system were prepared by conventional melting and annealing technique, and the transparent oxyfluoride glass-ceramics containing CaF2 nano-crystallines were obtained by controlled heat-treatment. The effect of heat-treatment schedules on the crystallization behavior and the microstructure of the glass-ceramics were analyzed by differential scanning caborimetry (DSC) analysis, X-ray diffraction (XRD) analysis, infrared (IR) spectrum and scanning electron microscopy (SEM). The sole CaF2 crystalline phase was confirmed by XRD, the spherical CaF2 nano-crystallines at about 20~100nm embed homogeneously among the glassy matrix after crystallization by SEM observation. The size of CaF2 grains grew with the increase of crystallization temperature and holding time. Te and Si atoms existed in [TeO3] and [SiO4] forms. Part of Al atoms existed in the form of [AlO4] and formed network together with [SiO4] tetrahedron. The other Al atoms acted as modifiers in the form of [AlO6]. The transmittance of glass-ceramics can reach 85% in visible light and 90% in infrared waveband. The novel transparent oxyfluoride tellurite glass-ceramics are excellent matrix materials in up-conversion luminescence field.

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The Study of Crystallization Dynamics of Amorphous Precursor Fe70Mo5Cr4Nb6B15 Alloy

Revista de Chimie ◽

10.37358/rc.18.2.6097 ◽

2018 ◽

Vol 69 (2) ◽

pp. 318-320

Author(s):

Konrad Gruszka ◽

Jakub Rzacki ◽

Marcin Nabialek

Keyword(s):

Heat Treatment ◽

Crystallization Process ◽

Amorphous Structure ◽

X Ray Diffraction ◽

Isothermal Heating ◽

Amorphous Precursor ◽

Crystalline Phases ◽

X Ray ◽

Crystallization Dynamics

The paper presents the results of studying the dynamics of the crystallization process for the samples subjected to three separate processes of isothermal heating with three different energy in the process. For this purpose, a series of samples prepared in the form of a ribbon of an amorphous structure, as confirmed from X-ray diffraction were then subjected to a controlled annealing. The research of samples after heat treatment revealed the presence of different crystalline phases that are characterized by different nucleation energies.

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An Investigation toward the Nano-Crystallization of Fe55Cr18Mo7B16C4 Bulk Amorphous Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.3858 ◽

2011 ◽

Vol 383-390 ◽

pp. 3858-3862

Author(s):

S. Ahmadi ◽

H.R. Shahverdi ◽

S.S. Saremi

Keyword(s):

Amorphous Alloy ◽

Crystallization Process ◽

Three Dimensional ◽

Bulk Amorphous Alloy ◽

Differential Scanning Calorimetric ◽

X Ray Diffraction ◽

Heating Rates ◽

Diffusion Controlled ◽

Average Size ◽

Dsc Curves

Nano- crystallization of Fe55Cr18Mo7B16C4 bulk amorphous alloy has been analyzed by X- ray diffraction, differential scanning calorimetric test, and TEM observations in this research. In practice, crystallization and growth mechanism were evaluated using DSC tests in four different heating rates (10, 20, 30, 40 K/min) and kinetic models. A two -step crystallization process was observed in the alloy in which α – Fe, Fe23B6, and Fe3C phases were crystallized in the structure after annealing process. In addition, activation energy for the first step of crystallization process (i.e. α – Fe phase) was measured to be 276 (kj/mol) and 290 (kj/mol) according to Kissinger and Ozawa models respectively. Avrami exponent calculated from DSC curves was 2 and a three -dimensional diffusion controlled mechanism with decreasing nucleation rate was observed in the alloy. Further, it is known from the TEM observations that crystalline α – Fe phase nucleated in structure of the alloy in an average size of 10 nm and completely mottled morphology.

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The Effect of Heat Treatment on the Corrosion Resistance of Fe-Based Amorphous Alloy Coating Prepared by High Velocity Oxygen Fuel Method

Materials ◽

10.3390/ma14247818 ◽

2021 ◽

Vol 14 (24) ◽

pp. 7818

Author(s):

Chun-Ying Lee ◽

Hung-Hua Sheu ◽

Leu-Wen Tsay ◽

Po-Sen Hsiao ◽

Tzu-Jing Lin ◽

...

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Amorphous Alloy ◽

High Velocity ◽

Annealing Temperature ◽

Annealing Treatment ◽

Alloy Coating ◽

Corrosion Current ◽

High Velocity Oxygen Fuel ◽

Oxygen Fuel

In this study, Fe40Cr19Mo18C15B8 amorphous coatings were prepared using high velocity oxygen fuel (HVOF) technology. Different temperatures were used in the heat treatment (600 °C, 650 °C, and 700 °C) and the annealed coatings were analyzed by DSC, SEM, TEM, and XRD. XRD and DSC results showed that the coating started to form a crystalline structure after annealing at 650 °C. From the SEM observation, it can be found that when the annealing temperature of the Fe-based amorphous alloy coating reached 700 °C, the surface morphology of the coating became relatively flat. TEM observation showed that when the annealing temperature of the Fe-based amorphous alloy coating was 700 °C, crystal grains in the coating recrystallized with a grain size of 5–20 nm. SAED analysis showed that the precipitated carbide phase was M23C6 phase with different crystal orientations (M = Fe, Cr, Mo). Finally, the corrosion polarization curve showed that the corrosion current density of the coating after annealing only increased by 9.13 μA/cm2, which indicated that the coating after annealing treatment still had excellent corrosion resistance. It also proved that the Fe-based amorphous alloy coating can be used in high-temperature environments. XPS analysis showed that after annealing FeO and Fe2O3 oxide components increased, and the formation of a large number of crystals in the coating resulted in a decrease in corrosion resistance.

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