scholarly journals Performance of TiB2 Wettable Cathode Coating

Minerals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 27
Author(s):  
Bo Yang ◽  
Ruzhen Peng ◽  
Dan Zhao ◽  
Ni Yang ◽  
Yanqing Hou ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Plasma Spraying ◽  
Liquid Aluminum ◽  
Atmospheric Plasma ◽  
Carbon Block ◽  
Graphite Cathode ◽  
X Ray ◽  
Salt Corrosion ◽  
Cathode Carbon ◽  
Tib2 Coating

A TiB2 wettable cathode coating was deposited on a graphite carbon cathode material via atmospheric plasma spraying (APS). The microstructure and phase composition of the TiB2 coating were analyzed via scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). The wettability and corrosion resistance of the coating were studied in a molten-aluminum electrolytic system. The results showed that the surface of the TiB2 coating prepared via plasma spraying was flat and that the main phase of the coating was TiB2. The wettability between the TiB2 coating and liquid aluminum was better than that between graphite cathode carbon block and liquid aluminum. The abilities of the TiB2 coating and graphite cathode carbon block to resist sodium (Na) penetration and prevent molten salt corrosion were compared through a corrosion test. The TiB2 coating was found to have better resistance to Na penetration and better refractory cryolite corrosion resistance than graphite cathode carbon block.

Microstructure and Corrosion Resistance of Fe-Based Amorphous Coating Prepared Atmospheric Plasma Spraying

2012 ◽  
Vol 557-559 ◽  
pp. 1768-1771
Author(s):  
Xiao Bing Zhao ◽  
Zhi Hui Ye
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Plasma Spraying ◽  
Amorphous Powder ◽  
Atmospheric Plasma Spraying ◽  
Atmospheric Plasma ◽  
Amorphous Coating ◽  
X Ray Diffraction ◽  
X Ray ◽  
Steel Substrates

Fe-based amorphous coating was prepared on stainless steel substrates by atmospheric plasma spraying (APS) using Fe-based amorphous powder as feedstock. Microstructures of the coating were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM). The corrosion behavior of coating and stainless steel were evaluated respectively in 3.5% NaCl, 10% NaOH and 1 mol/L H2SO4 aqueous solutions by electrochemical workstation. The results indicated that the coating was composed of most amorphous phase and some Fe-Cr crystalline phase. The coating exhibited the better corrosion resistance in H2SO4 solution, while the worse in NaOH.

THE PERFORMANCES OF TiN-TiB2 COATING PREPARED BY REACTIVE PLASMA SPRAYING

2012 ◽  
Vol 19 (03) ◽  
pp. 1250028
Author(s):  
JING MA ◽  
JIANWEN HU ◽  
DONGQING YAN ◽  
ZHENGPING MAO
Keyword(s):  
Corrosion Resistance ◽  
Carbon Steel ◽  
Plasma Spraying ◽  
Nacl Solution ◽  
Reactive Plasma Spraying ◽  
Reactive Plasma ◽  
Plasma Sprayed Coatings ◽  
Plasma Sprayed ◽  
Steel Substrates ◽  
Tib2 Coating

Reactive plasma sprayed coatings were prepared on carbon steel substrates with Ti and B4C as starting materials. Two kinds of gases ( Ar and N2 ) were used as feeding gases for powders, respectively. 10 wt.% Cr was added in the powders as binder to increase the bond strength of the coating. The phases, microstructure, micro-hardness and corrosion polarization behavior in 3.5 wt.% NaCl solution of the two coatings were studied. The results show that TiN-TiB2 coatings were prepared under both conditions. The two coatings have typically laminated structure. However, the coating prepared with Ar as feeding gas has higher porosity and some unmelted Cr particles. It also contains certain content of titanium oxides. The microhardness of coating prepared with Ar as feeding gas is lower due to its higher porosity, unmelted Cr particles and some amounts of TiO2 . The corrosion resistance of TiN-TiB2 coating prepared with Ar as feeding gas in 3.5 wt.% NaCl solution is worse than that of the coating prepared with N2 as feeding gas. Yet the corrosion resistance of reactive plasma sprayed TiN-TiB2 coating is improved greatly compared with that of carbon steel. The thermodynamic analysis of reactive plasma spraying process is also discussed.

scholarly journals YAlO3—A Novel Environmental Barrier Coating for Al2O3/Al2O3–Ceramic Matrix Composites

Coatings ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 609 ◽  
Author(s):  
Caren Gatzen ◽  
Daniel Emil Mack ◽  
Olivier Guillon ◽  
Robert Vaßen
Keyword(s):  
Plasma Spraying ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Atmospheric Plasma ◽  
Aluminum Silicate ◽  
Matrix Composites ◽  
Surface Pretreatment ◽  
X Ray ◽  
Environmental Barrier ◽  
Barrier Coating

Ceramic matrix composites (CMCs) are promising materials for high-temperature applications. Environmental barrier coatings (EBCs) are needed to protect the components against water vapor attack. A new potential EBC material, YAlO3, was studied in this paper. Different plasma-spraying techniques were used for the production of coatings on an alumina-based CMC, such as atmospheric plasma spraying (APS) and very low pressure plasma spraying (VLPPS). No bond coats or surface treatments were applied. The performance was tested by pull–adhesion tests, burner rig tests, and calcium-magnesium-aluminum-silicate (CMAS) corrosion tests. The samples were subsequently analyzed by means of X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Special attention was paid to the interaction at the interface between coating and substrate. The results show that fully crystalline and good adherent YAlO3 coatings can be produced without further substrate preparation such as surface pretreatment or bond coat application. The formation of a thin reaction layer between coating and substrate seems to promote adhesion.

scholarly journals Frictional Wear and Corrosion Behavior of AlCoCrFeNi High-Entropy Alloy Coatings Synthesized by Atmospheric Plasma Spraying

Entropy ◽  
2020 ◽  
Vol 22 (7) ◽  
pp. 740
Author(s):  
Yongkun Mu ◽  
Liangbo Zhang ◽  
Long Xu ◽  
Kondagokuldoss Prashanth ◽  
Nizhen Zhang ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Plasma Spraying ◽  
Corrosion Behavior ◽  
Atmospheric Plasma Spraying ◽  
Atmospheric Plasma ◽  
High Entropy Alloy ◽  
High Entropy ◽  
Frictional Wear ◽  
Wear And Corrosion ◽  
Wear And Corrosion Resistance

High-entropy alloy coatings (HEAC) exhibit good frictional wear and corrosion resistances, which are of importance for structure materials. In this study, the microstructure, surface morphology, hardness, frictional wear and corrosion resistance of an AlCoCrFeNi high-entropy alloy coating synthesized by atmospheric plasma spraying (APS) were investigated. The frictional wear and corrosion resistance of the coating are simultaneously improved with an increase of the power of APS. The influence of the APS process on the microstructure and mechanical behavior is elucidated. The mechanisms of frictional wear and corrosion behavior of the AlCoCrFeNi HEAC are discussed in detail.

Ablation Behavior of HfC Coating Prepared by Supersonic Plasma Spraying for SiC-Coated C/C Composites

2015 ◽  
Vol 24 (5) ◽  
pp. 096369351502400 ◽  
Author(s):  
Yang Yang ◽  
Kezhi Li ◽  
Hejun Li
Keyword(s):  
Plasma Spraying ◽  
Atmospheric Plasma Spraying ◽  
Atmospheric Plasma ◽  
X Ray Diffraction ◽  
Dense Structure ◽  
X Ray ◽  
Ablation Resistance ◽  
Supersonic Plasma ◽  
Centre Region ◽  
Supersonic Atmospheric Plasma Spraying

In order to improve the ablation resistance of C/C composites HfC coating was deposited on the surface of SiC-coated C/C composites by supersonic atmospheric plasma spraying. The microstructure and morphology of the different coatings were characterized by Scanning Electron Microscopy, X-ray diffraction. The ablation test of samples was carried out with an oxyacetylene torch. The coating exhibits dense structure and good ablation resistance. After ablation for 30s, the linear and mass ablation rates of the coating are 0.59 μm/s and 0.6 mg/s, respectively. In ablation centre region, a HfO2 layer is formed on the surface of sample after 30s ablation, and it can protect C/C composites from ablation.

Atmospheric Plasma Spraying of Run-in Coatings for Twin-Screw Compressors

2000 ◽  
Author(s):  
Fr.-W. Bach ◽  
T. Duda ◽  
W. Unterberg ◽  
L.A. Josefiak
Keyword(s):  
Corrosion Resistance ◽  
Plasma Spraying ◽  
Atmospheric Plasma Spraying ◽  
Yttria Stabilized Zirconia ◽  
Thermal Spray Coatings ◽  
Atmospheric Plasma ◽  
Stabilized Zirconia ◽  
Spray Coatings ◽  
Twin Screw ◽  
Screw Rotors

Abstract This paper examines the potential of thermal spray coatings for manufacturing and repairing twin-screw rotors. The coatings evaluated were produced by atmospheric plasma spraying (APS). Tests show that 7% yttria stabilized zirconia (ZrO27Y2O3) coatings provide sufficient run-in characteristics and corrosion resistance. The coatings, along with a NiCrAl bond coat, were applied to various substrate materials.

The Effect of Spraying Conditions on the Corrosion Resistance of Titanium Coatings for Surgical Implants

1996 ◽  
Author(s):  
B. Normand ◽  
F. Renaud ◽  
C. Coddet ◽  
F. Tourenne
Keyword(s):  
Corrosion Resistance ◽  
Plasma Spraying ◽  
Corrosion Behaviour ◽  
Electrochemical Techniques ◽  
Deposition Process ◽  
Atmospheric Plasma Spraying ◽  
Atmospheric Plasma ◽  
Localized Corrosion ◽  
Titanium Coating ◽  
Pmma Bone Cement

Abstract One cause of aseptic loosening of total hip replacement (THR) results from the hard polymetylmethacrylate (PMMA) bone cement debris embedded within some of acetabular cups [1]. To prevent this failure, PMMA can be replaced by a titanium coating with a specific roughness to promote the bone bonding. In this work, inert and atmospheric plasma spraying was used to coat Ti.6A1.4V implants with titanium.] In order to evaluate the effect of the deposition process on the coating corrosion resistance, different electrochemical techniques were implemented in physiological (i. e., Ringer) and in acidic solutions. Results show that the spraying parameters and the coating morphology affect the corrosion behaviour. Thus, if the reactivity is not affected by the pH evolution, the pitting sensitivity depends on the process. It was found that coatings deposited under inert gas are free of oxides and dense, even when the atmosphere contains some hydrogen. In that case a significant improvement of the intrinsic localized corrosion resistance is observed versus deposits obtained using atmospheric plasma spraying.

scholarly journals Microstructural Analysis and Tribological Behavior of Ti-Based Alloys with a Ceramic Layer Using the Thermal Spray Method

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1216
Author(s):  
Madalina Simona Baltatu ◽  
Petrica Vizureanu ◽  
Andrei Victor Sandu ◽  
Corneliu Munteanu ◽  
Bogdan Istrate
Keyword(s):  
Mechanical Properties ◽  
Corrosion Resistance ◽  
Healing Process ◽  
Microstructural Analysis ◽  
Titanium Substrate ◽  
Stress Shielding ◽  
Atmospheric Plasma ◽  
Morphological Aspect ◽  
Thin Coatings ◽  
X Ray

The present article focuses on a recently developed new system of alloys (Ti15MoSi) coated with ZrO2. The thin coatings deposition of ZrO2 on titanium alloys can be a solution to improve their corrosion resistance, biocompatibility, and to extend their long life with the human tissue. In order to improve the corrosion resistance, atmospheric plasma spraying coatings with zirconia have been performed. These coatings present a homogenous aspect with very few cracks. The novelty of the research is that zirconia is much stable in the simulated body fluids and presents no harm effects to the healing process of the bone. To analyze the thin coatings deposition, mechanical properties, chemical structure, and corrosion resistance were examined by a modulus of elasticity, X-ray diffraction (XRD), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS), and linear polarization. The results reveal that Young’s modulus shows a low value (51 GPa for Ti15Mo0.5Si-ZrO2 and 48 GPa for Ti15Mo-ZrO2) and the XRD patterns show the presence of β-Ti and ZrO2 phases having a tetragonal crystalline structure. The research highlighted the morphological aspect of zirconia coatings on the new alloy titanium substrate, being an adherent compact coating with significantly improved corrosion resistance. Moreover, the mechanical properties are similar to the biological bone, which will avoid the stress shielding of the implant with bone tissue.

Electron behavior in the gaseous environment of the ESEM chamber

1996 ◽  
Vol 54 ◽  
pp. 838-839 ◽  
Author(s):  
S.A. Wight
Keyword(s):  
Secondary Electron ◽  
High Vacuum ◽  
Beam Current ◽  
Chamber Pressure ◽  
Environmental Scanning ◽  
Carbon Block ◽  
Faraday Cup ◽  
X Ray ◽  
Gaseous Environment ◽  
Working Distance

Measurements of electrons striking the sample in the Environmental Scanning Electron Microscope (ESEM) are needed to begin to understand the effect of the presence of the gas on analytical measurements. Accurate beam current is important to x-ray microanalysis and it is typically measured with a faraday cup. A faraday cup (Figure 1) was constructed from a carbon block embedded in non-conductive epoxy with a 45 micrometer bore platinum aperture over the hole. Currents were measured with an electrometer and recorded as instrument parameters were varied.Instrument parameters investigated included working distance, chamber pressure, condenser percentage, and accelerating voltage. The conditions studied were low vacuum with gaseous secondary electron detector (GSED) voltage on; low vacuum with GSED voltage off; and high vacuum (GSED off). The base conditions were 30 kV, 667 Pa (5 Torr) water vapor, 100,000x magnification with the beam centered inside aperture, GSED voltage at 370 VDC, condenser at 50%, and working distance at 19.5 mm. All modifications of instrument parameters were made from these conditions.

Sign in / Sign up

Export Citation Format

Share Document