Influence of Air Plasma Spraying Process Parameters on Ceramic Layer in Thermal Barrier Coatings

2017 ◽  
Vol 267 ◽  
pp. 207-211
Author(s):  
Tadeusz Kubaszek ◽  
Marek Góral
Keyword(s):  
Plasma Spraying ◽  
Process Parameters ◽  
Plasma Plume ◽  
Ceramic Powder ◽  
Ceramic Coatings ◽  
Air Plasma ◽  
Fine Grain ◽  
Contour Plots ◽  
Molten Particle ◽  
Sprayed Coating

The aim of this study was to examine the possibility of application in APS process Yttria Stabilized Zirconia (YSZ) – Metco 6700 ceramic powder normally used in Low Pressure Plasma Spraying (LPPS) method. Powder grain size is around 10 µm. Parameters such as chemical composition of plasma gases and current were changed to obtain the best result. The experiment was divided into two stages. Firstly, temperature, velocity and size of a molten particle of ceramic powder inside plasma plume were measured via DPV eVolution equipment (TECNAR company) during a different set of process parameters. Plasma plume was also scanned to obtain cross-section contour plots of mentioned properties of the molten particle. Secondly, the same processes were repeated to deposit TBC coatings onto sheet metal to examine the structure.The obtained results showed that it is possible to use fine-grain YSZ powder Metco 6700 for APS process. Obtained ceramic coatings had a thickness from 100 to 240 µm. The plasma sprayed coating was characterised by a smooth surface. The measurement of spraying parameters showed the uniform temperature, velocity and particle size of the powder inside plasma plume.

Supersonic air-plasma spraying of carbide ceramic coatings

2020 ◽  
Author(s):  
Viktor Kuzmin ◽  
Igor Gulyaev ◽  
Dmitriy Sergachev ◽  
Sergey Vashchenko ◽  
Anatoliy Lysakov ◽  
...  
Keyword(s):  
Plasma Spraying ◽  
Ceramic Coatings ◽  
Air Plasma ◽  
Air Plasma Spraying

Microstructure Characterization of TBC Layers of Gd2Zr2O7 Type

2011 ◽  
Vol 312-315 ◽  
pp. 439-444 ◽  
Author(s):  
Grzegorz Moskal
Keyword(s):  
Plasma Spraying ◽  
Visual Assessment ◽  
Ceramic Coatings ◽  
Ceramic Layer ◽  
Composition Analysis ◽  
Air Plasma ◽  
New Type ◽  
Microscopy Method ◽  
Qualitative Characteristics

The paper presents microstructural assessment results of thermal barrier coatings deposited by plasma spraying of powders with the formula Gd2Zr2O7. Standard parameters of the air plasma spraying (APS) method were used. A visual assessment of layers and quantitative and qualitative characteristics of an outer ceramic layer with the laser microscopy method were performed. Roughness and other geometric parameters describing the TBC surface were determined. Phase composition analysis of the ceramic layer was also carried out. Microstructural assessment of the layers for meeting the assessment criteria of the ceramic coatings was also carried out. The bondcoat and ceramic layer porosity assessment was performed. The TBC system general quality was assessed for presence of cracks, delamination and massive porosity. It was found that the new type of layers obtained meet the quality requirements used for assessment of the conventional layers obtained by spraying 8YSZ zirconia.

High Quality Ceramic Coatings Sprayed by High Efficiency Hypersonic Plasma Spraying Gun

2005 ◽  
Vol 475-479 ◽  
pp. 3981-3984 ◽  
Author(s):  
Sheng Zhu ◽  
Bin Shi Xu ◽  
Jiu Kun Yao
Keyword(s):  
Plasma Spraying ◽  
Ceramic Coating ◽  
High Efficiency ◽  
Low Cost ◽  
Ceramic Coatings ◽  
Air Plasma ◽  
Air Plasma Spraying ◽  
Ceramic Powders ◽  
Tio2 Ceramic ◽  
Spraying Process

This paper introduced the structure of the high efficiency hypersonic plasma spraying gun and the effects of hypersonic plasma jet on the sprayed particles. The optimised spraying process parameters for several ceramic powders such as Al2O3, Cr2O3, ZrO2, Cr3C2 and Co-WC were listed. The properties and microstructure of the sprayed ceramic coatings were investigated. Nano Al2O3-TiO2 ceramic coating sprayed by using the high efficiency hypersonic plasma spraying was also studied. Compared with the conventional air plasma spraying, high efficiency hypersonic plasma spraying improves greatly the ceramic coatings quality but at low cost.

The Influence of Process Parameters on Structure of Ceramic Coatings Deposited by PS-PVD Method

2017 ◽  
Vol 267 ◽  
pp. 243-247 ◽  
Author(s):  
Marek Góral ◽  
Tadeusz Kubaszek
Keyword(s):  
Process Parameters ◽  
Feed Rate ◽  
Ceramic Powder ◽  
Turbine Blades ◽  
Oxide Coating ◽  
Ceramic Coatings ◽  
Columnar Structure ◽  
Powder Feed Rate ◽  
Influence Of Process Parameters ◽  
Powder Feed

Thermal Barrier Coatings (TBC) is the most advanced system for protection of turbine blades and vanes against high temperature, and oxidation. They are used in most advanced jet engines. In present article the new Plasma Spray Physical Vapour Deposition Technology was used to obtain yttria stabilized zirconia oxide coating with columnar structure. In research the different process parameters were changed. It was observed that powder feed rate had big influence on coating thickness. The large amount of Ar in plasma gasses combined with high powder feed rate resulted in partial evaporation of ceramic powder and splat-type structure. The same effect was observed when the power current was decreased form 2400 to 1600 A as well as pressure was increased to 200 Pa when the powder feed rate was 30 g/min. The obtained results showed that full evaporation of ceramic powder requires very low feed rate of ceramic material (2 g/min), high power current and high He content into plasma.

Study of Microstructure and Mechanical Properties of Yttrium Stabilized Zirconia Coating Deposited by Air Plasma Spray

2013 ◽  
Author(s):  
Chris P. Leither ◽  
Lauren E. Roy ◽  
Fardad Azarmi ◽  
X. W. Tangpong
Keyword(s):  
Mechanical Performance ◽  
Microstructural Characterization ◽  
Ceramic Coatings ◽  
Air Plasma ◽  
Zirconia Coating ◽  
Stabilized Zirconia ◽  
Free Standing ◽  
Bending Modulus ◽  
Sprayed Coating ◽  
Plasma Sprayed

Ceramic materials have been used extensively in different industries due to their excellent properties in high temperature environment. Thermally sprayed ceramic coatings offer outstanding properties which make them suitable candidate for advanced applications. These coatings exhibit excellent wear resistant properties with high adhesion strength. Depending on the application, ceramic coatings can be subjected to in-plane or out-of-plane loading during service. When the components are exposed to extreme change in temperature, consistent expansion, and shrinkage of the materials will cause crack initiation and propagation, resulting in spallation of the coating and consequently failure of the components. In this study, mechanical performance of plasma sprayed Yttrium stabilized Zirconia coating was investigated. A powder mixture of Yttrium stabilized Zirconia (ZrO2−8Y2O3) was air plasma sprayed on a cast iron substrate. Microstructural characterization of the as-sprayed coating was performed to evaluate the microstructural uniformity of the deposited samples using scanning electron microscopy (SEM). Three-point bend tests were performed to measure bending modulus of the free standing as-sprayed coating samples. Knoop indentation technique was also used as an alternate method to determine the modulus of the coating. Damping properties of the samples were also evaluated. This study pays special attention to the dependency of the mechanical performance on the microstructural characteristics of the thermal sprayed ceramic coatings.

High-Performance Ceramic Coatings Sprayed via Novel Supersonic Plasma Spraying System

2007 ◽  
Vol 280-283 ◽  
pp. 1203-1206 ◽  
Author(s):  
Sheng Zhu ◽  
Bin Shi Xu
Keyword(s):  
Plasma Spraying ◽  
High Performance ◽  
Gas Flow ◽  
Low Cost ◽  
Ceramic Coatings ◽  
Air Plasma ◽  
Plasma Gun ◽  
Supersonic Plasma ◽  
Particle Velocities ◽  
Supersonic Plasma Jet

A novel supersonic plasma spraying system was developed with a maximum power of 80 kW and a maximum working gas flow of 6 m3/h, at which gas and particle velocities of 2400 and 600 m/s can be achieved respectively. This paper deals with novel supersonic plasma spraying system design, the structure of novel supersonic plasma gun includes a special Laval nozzle as the single anode and inner powder supply, and the mechanisms of supersonic plasma jet as well as the effects on the sprayed particles. The spraying process parameters of several ceramic powders such as Al2O3, Cr2O3, ZrO2, Cr3C2 and Co-WC were optimized. The properties and microstructure of the sprayed ceramic coatings were investigated. Nano Al2O3-TiO2 ceramic coating sprayed by using novel supersonic plasma spraying was also studied. Novel supersonic plasma spraying improves greatly ceramic coatings quality compared with conventional air plasma spraying (Metco 9M), as well as it has lower energy and gas exhaustion compared with high power supersonic plasma spraying (Plazjet), which can spray high-performance ceramic coatings at low cost.

Oxidation Control in Atmospheric Plasma Spraying: Comparison Between Ar/H2/He and Ar/H2 Mixtures

1998 ◽  
Author(s):  
A. Denoirjean ◽  
O. Lagnoux ◽  
P. Fauchais ◽  
V. Sember
Keyword(s):  
Plasma Spraying ◽  
Flow Model ◽  
Plasma Plume ◽  
Air Entrainment ◽  
Thermomechanical Properties ◽  
Plasma Jets ◽  
Atmospheric Plasma ◽  
Air Plasma ◽  
Air Plasma Spraying ◽  
Enthalpy Probe

Abstract Plasma spraying of metals and metallic alloys performed in controlled atmosphere or soft vacuum results in coatings with a low oxidation level and excellent thermomechanical properties. Unfortunately, the spraying cost is drastically increased by one or two orders of magnitude compared to air plasma spraying (APS). Thus the minimisation of oxidation during APS is a key issue for the development of such coatings. Oxygen concentrations sucked into plasma jets have been measured by an enthalpy probe linked to a mass spectrometer. This technique allows to determine simultaneously plasma composition, temperature and velocity distributions within the plasma plume. Results have been compared to those obtained with a two-dimensional turbulent flow model. The obtained results have shown that surrounding air entrainment is reduced when using adequate Ar/Hj/He mixtures which viscosity is higher than that of Ar/H, mixtures, limiting the turbulence in the jet fringes and pumping of the surrounding atmosphere.

Titanium Based Composite Coatings Deposited by High Velocity Oxygen Fuel (HVOF) and Plasma Spraying Methods

2013 ◽  
Vol 551 ◽  
pp. 127-132
Author(s):  
Asma Salman ◽  
Brian Gabbitas ◽  
De Liang Zhang
Keyword(s):  
Plasma Spraying ◽  
High Velocity ◽  
Composite Coatings ◽  
High Energy ◽  
High Velocity Oxygen Fuel ◽  
Air Plasma ◽  
Feedstock Powder ◽  
Hvof Spraying ◽  
Sprayed Coating ◽  
Oxygen Fuel

The study involves a special class of composites called interpenetrating phase composites (IPCs). The Ti(Al,O)/Al2O3 composite was produced using high energy mechanical milling of a mixture of TiO2 and Al followed by a high temperature self-propagating reaction. Characteristics of the feedstock powder were improved by treating it with an organic binder. The feedstock powder was thermally sprayed on to a substrate using high velocity oxygen fuel (HVOF) and air plasma spraying methods. The spraying methods resulted in coatings with significantly different microstructures. Compared with plasma sprayed coating, the coating produced by a HVOF spraying method showed a much finer and densely packed microstructure.

Sign in / Sign up

Export Citation Format

Share Document