The Influence of Spray Parameters on the Characteristics of Hydroxyapatite In-Flight Particles, Splats and Coatings by Micro-plasma Spraying

2018 ◽  
Vol 27 (4) ◽  
pp. 667-679 ◽  
Author(s):  
Xiao-mei Liu ◽  
Ding-yong He ◽  
Yi-ming Wang ◽  
Zheng Zhou ◽  
Guo-hong Wang ◽  
...  
Keyword(s):  
Plasma Spraying ◽  
Influence Of Spray Parameters ◽  
Spray Parameters

Plasma Spraying of Solid Oxide Fuel Cell Components

1997 ◽  
Author(s):  
G. Schiller ◽  
M. Müller ◽  
R. Ruckdäschel ◽  
R. Henne ◽  
M. Lang
Keyword(s):  
Plasma Spraying ◽  
Plasma Spray ◽  
Solid Oxide ◽  
Rf Plasma ◽  
Spray Parameters ◽  
Oxide Fuel ◽  
Bipolar Plates ◽  
Metallic Bipolar Plates ◽  
Protective Layers ◽  
Near Net Shape

Abstract The central components for solid oxide fuel cells (SOFC) are the electrodes-electrolyte multilayer arrangement (PEN) and the separating bipolar plates. The PEN (Positive electrode- Electrolyte-Negative electrode) assembly consists of a dense gastight yttria-stabilized zirconia (YSZ) electrolyte and porous electrodes for which usually Ni-YSZ cermet anode and Sr-doped LaMnO3 cathode layers are used. The various PEN units are connected in a cell stack by bipolar plates which are either metallic or ceramic ones. Furthermore, a protective layer on the metallic bipolar plates consisting of a chromium alloy is required to prevent chromium evaporation leading to a rapid and strong degradation of the SOFC performance. At the DLR Stuttgart both the DC and the RF vacuum plasma spraying technique have been further developed and adapted to meet the requirements for the manufacture of the different SOFC components. The DCVPS process using specially developed Laval-like nozzles is especially appropriate to the production of thin and dense coatings as required for the electrolyte and the protective layers. However, applying special spray parameters and nozzles it is also possible to deposit porous electrode layers. The production of the entire PEN arrangement in one consecutive DC-VPS process is the objective of the actual development. On the other hand, the RF plasma spray technique is suitable for the near net-shape production of bulk components such as the metallic bipolar plate. The development of the deposition processes for the production of SOFC components using DC and RF plasma spray methods and the results obtained concerning PEN fabrication, deposition of protective layers and the near net-shape production of metallic bipolar plates are presented in the paper.

Plasma Spraying of Self-Lubricating Cr2O3-CaF2 Coatings

1997 ◽  
Author(s):  
F. Vos ◽  
L. Delaey ◽  
M. De Bonte ◽  
L. Froyen
Keyword(s):  
Plasma Spraying ◽  
Matrix Material ◽  
Production Method ◽  
Atmospheric Plasma ◽  
Spray Parameters ◽  
The Matrix ◽  
Preparation Step ◽  
Plasma Sprayed ◽  
The Relationship ◽  
Selection Of

Abstract Results are presented of a project analysing the relationship between the production parameters of plasma sprayed self-lubricating Cr2O3-CaF2 coatings and their structural, wear and lubricating properties. The production method consists of a preparation step where a powder blend of the matrix material (Cr203) and solid lubricant (CaF2) is agglomerated, followed by atmospheric plasma spraying (APS) of the agglomerates. Selection of the most appropriate agglomeration and plasma spray parameters as well as the microstructure of the coatings will be discussed.

TRIBOLOGICAL PROPERTIES OF Al2O3 + TiO2 COATINGS MANUFACTURED BY PLASMA SPRAYING

Tribologia ◽  
2019 ◽  
Vol 283 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Leszek ŁATKA ◽  
Aneta NIEMIEC ◽  
Monika MICHALAK ◽  
Paweł SOKOŁOWSKI
Keyword(s):  
Plasma Spraying ◽  
Dry Friction ◽  
Plasma Torch ◽  
Spray Parameters ◽  
Good Adhesion ◽  
Spray Distance ◽  
Compact Structure ◽  
Tio2 Coatings ◽  
Made In ◽  
Ball On Disc

In the paper the results of tribological, microscopic, and mechanical research of Al2O3 + TiO2 coatings manufactured by plasma spraying are presented. The feeding material was a powder Al2O3 + 13 wt.% TiO2 (Metco 6221, OerlikonMetco) with grain size – 45 ± 15 μm. The cylinder substrates made from stainless steel (X5CrNi18-10) had a diameter equal to 25 mm and 2 mm of thickness. The variable spray parameters were plasma torch velocity in terms of substrate and spray distance. The morphology of obtained coatings was tested by scanning electron microscope (SEM), and the microstructure was investigated by light optical microscopy (LOM) and SEM. The results of mechanical properties examinations revealed the dependence of the microhardness and fracture toughness on the spray parameters. Tribological examinations were made in the ball-on-disc mode in technical dry friction conditions. Two loads were used, 5 N and 10 N. Based on the carried out tests, it could be concluded that a shorter spray distance and a reduction of the torch velocity allows one to achieve a more compact structure, which is characterized by good adhesion at the coating-substrate interface (in range from 11 to 14 MPa) and good wear resistance.

scholarly journals Analysis of the Influence of Different Parameters on Droplet Characteristics and Droplet Size Classification Categories for Air Induction Nozzle

Agronomy ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 256
Author(s):  
Juan Liao ◽  
Xiwen Luo ◽  
Pei Wang ◽  
Zhiyan Zhou ◽  
Chris C. O’Donnell ◽  
...  
Keyword(s):  
Droplet Size ◽  
Droplet Diameter ◽  
Dynamic Surface Tension ◽  
Analysis Of Covariance ◽  
Influence Of Spray Parameters ◽  
Spray Parameters ◽  
Dynamic Surface ◽  
Nozzle Orifice ◽  
Before And After ◽  
American Society

Droplet characteristics are identified as essential factors in agricultural spray application. The aims of this study were to analyse the influence of spray parameters on droplet characteristics and to determine possible candidate sprays that would produce the same droplet size categorizations as the American Society of Agricultural and Biological Engineers (ASABE) standard S-572.1 for air induction nozzles (AINs). Six different orifice sizes of the Billericay Farm Services (BFS) air induction (AI) flat fan hydraulic nozzles (the air bubblejet) were examined at different spray pressures (200 kPa, 300 kPa, 400 kPa, 500 kPa, 600 kPa and 700 kPa) and concurrent air velocities (2 m/s, 3 m/s, 4 m/s and 5 m/s). The influences of spray parameters on the droplet characteristics were analysed using analysis of covariance (ANCOVA) and analysis of variance (ANOVA). Results showed that: (1) The values of droplet characteristics and the results of ANOVA were significantly different before and after eliminate the influence of dynamic surface tension (DST) on droplet characteristics by ANCOVA; (2) (a) the reduction rates of the droplet diameter sizes decreased with increasing spray pressure; (b) air velocities of 2 m/s and 5 m/s resulted in smaller droplets reports, and air velocities of 3 m/s and 4 m/s are more suitable for agricultural spray applications; (c) a larger nozzle orifice size not always result in a larger droplet size and (3) Fine, Medium, Coarse, Very Coarse and Extremely Coarse droplet classification categories as the ASABE S-572.1 standard categorizations were determined to classify AINs.

Effect of Spray Parameters on the Plasma in High Pressure Plasma Spraying Up to 300 kPa

1998 ◽  
Author(s):  
S. Sodeoka ◽  
M. Suzuki ◽  
T. Inoue ◽  
K. Ueno
Keyword(s):  
High Pressure ◽  
Plasma Spraying ◽  
Gas Flow ◽  
High Plasma ◽  
Chamber Pressure ◽  
Spray Parameters ◽  
Electric Voltage ◽  
Flow Rates ◽  
Pressure Plasma ◽  
Spraying Parameters

Abstract To develop the spraying parameters for effective and safe operation of high pressure plasma spraying, the influence of nozzle bore diameter and plasma gas flow on the characteristics of plasma torch have been investigated under the chamber pressure ranging from 5 to 300 kPa. Large bore size allows high plasma gas flow rates without excessive increasing electric voltage, which is apt to damage the cathode. High flow rates (Ar: 1.3x10-3, H2: 1.3x10-4, He: 2.7x10-4 m3/s) is effective in imbuing more power into the plasma without nozzle damage under higher chamber pressures. The relationships among the parameters, such as the effective plasma power, the electric efficiency, the chamber pressure, the plasma gas flow and so on, were expressed qualitatively by a multiple regression analysis.

Influence of the Spray Parameters on the Transient Pressure within a Molten Particle Impacting onto a Flat Substrate

1997 ◽  
Author(s):  
G. Montavon ◽  
Z.G. Feng ◽  
C. Coddet ◽  
Z.Q. Feng ◽  
M. Domaszewski
Keyword(s):  
Particle Density ◽  
Substrate Surface ◽  
Element Model ◽  
Processing Parameters ◽  
Influence Of Spray Parameters ◽  
Spray Parameters ◽  
Transient Pressure ◽  
Flat Substrate ◽  
Molten Particle ◽  
The Impact

Abstract This paper is devoted to the investigation of the transient pressure occurring at the impact of a molten particle onto a flat substrate surface under different thermal spray conditions. In this paper, the mathematical model developed is based on the following assumptions: laminar, viscous and incompressible fluid; the mixed velocity-pressure model is employed to construct the finite element model. The choice of pressure penalty coefficient, which depends on the Reynolds number, is crucial for the results. This is discussed in this paper. The numerical results show that the pressure at the particle-substrate interface is strongly affected by the processing parameters, especially by the particle density and the impact velocity. The influence of spray parameters and material properties are also discussed.

scholarly journals Preparation and Performance Optimization of Original Aluminum Ash Coating Based on Plasma Spraying

Coatings ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 770 ◽  
Author(s):  
Hongjun Ni ◽  
Jiaqiao Zhang ◽  
Shuaishuai Lv ◽  
Xingxing Wang ◽  
Yu Zhu ◽  
...  
Keyword(s):  
Plasma Spraying ◽  
Plasma Spray ◽  
Performance Optimization ◽  
Gas Flow ◽  
Orthogonal Experiment ◽  
Angle Of Repose ◽  
Spray Parameters ◽  
Coating Properties ◽  
Industrial Solid Waste ◽  
And Performance

As an industrial solid waste, the original aluminum ash (OAA) will cause serious pollution to the air and soil. How to reuse the OAA has been a research difficulty. Thus, a method of preparing a plasma spray powder using OAA is proposed. The OAA was hydrolyzed and ball milled, and the flowability of original aluminum ash spray powder (OAASP) was evaluated by the angle of repose. The coating properties were determined via analyzing the microstructure and the phase of the coating, and the effects of plasma spray parameters on the coating properties were investigated by the orthogonal experiment to optimize spray parameters. The results show that the angle of repose of OAASP after granulation was less than 40°, which met the requirements of plasma spraying. When the spraying current was 600 A, the spraying voltage was 60 V, the main gas flow was 33 slpm, and the powder flow rate was 22 g/min, and the prepared original aluminum ash coating (OAAC) had excellent comprehensive performance. After the spraying process parameters were optimized, the microhardness of the coating was 606.54 HV, which is about twice the hardness of the substrate; the abrasion rate was 12.86 × 10−3 g/min; the porosity was 0.16%; and the adhesive strength was 16 MPa. When the amount of Al2O3 added was 50%, the hardness of the coating was increased by 17.61%.

Influence of Spray Parameters on Sliding Wear Properties of HVOF Sprayed Fe-Based Amorphous Coatings

2015 ◽  
Vol 723 ◽  
pp. 848-851
Author(s):  
Guang Liu ◽  
Zi Yun Zheng ◽  
Li Jia ◽  
Bing Ma ◽  
Lang Cui ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Sliding Wear ◽  
Influence Of Spray Parameters ◽  
Spray Parameters ◽  
Wear Properties ◽  
Amorphous Content ◽  
Spraying Parameters ◽  
Structure Of Coatings ◽  
Amorphous Powders ◽  
Amorphous Coatings

Amorphous powders of Fe-10.7%W-4.5%Cr-4.1%B-3.6%Ni-3.5%Si-2.1%Mo-1.2%C-0.7%Mn were sprayed under six sets of spraying parameters using high velocity oxy-fuel spraying. Phase structure of coatings as well as microstructure is found to be strongly affected by spraying parameters. Sliding wear resistance of amorphous coatings benefits significantly from less porosity and oxides. In addition, evidence correlation is found between amorphous content and wear resistance of coatings. Coating with the best wear resistance exhibits the wear rate of only 2.84×10-6 mm3/(N·m), equals 1.70% and 217% of cast 316L stainless and HVOF-sprayed Cr3C2-NiCr coating respectively.

Sign in / Sign up

Export Citation Format

Share Document