Relationships between Microstructural and Mechanical Properties of Plasma Sprayed AlSi-Polyester Composite Coatings: Application to Abradable Materials

Abradable coatings are widely used within aeroengines. These materials are applied onto the inner surface of compressor and turbine shroud sections using thermal spray processes, coating the periphery of the blade rotation path. The functionality of an abradable seal is to wear preferentially when rotating blades come into contact with it, while minimizing the over-tip clearance, and improving the overall efficiency of the engine. This study is concerned with the relationships between the microstructure and mechanical properties of atmospheric plasma sprayed AlSi-Polyester composite coatings.

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Microstructural Charactistics of Plasma Sprayed NiCrBSi Coatings and Their Wear and Corrosion Behaviors

Coatings ◽

10.3390/coatings11020170 ◽

2021 ◽

Vol 11 (2) ◽

pp. 170

Author(s):

Songqiang Huang ◽

Jingzhong Zhou ◽

Kuoteng Sun ◽

Hailiang Yang ◽

Weichen Cai ◽

...

Keyword(s):

Laser Scanning ◽

Acid Corrosion ◽

Composite Coatings ◽

Atmospheric Plasma ◽

Confocal Laser ◽

Formation Mechanisms ◽

Temperature Oxidation ◽

Surface Protection ◽

Plasma Sprayed ◽

Nicrbsi Coatings

Nickel-based alloys are commonly used as protective coating materials for surface protection applications owing to their superior resistance to corrosion, wear and high-temperature oxidation. It is urgent to study the fundamental mechanism between the structure and corrosion properties of the Nickel-base composite coatings. This paper, therefore, focuses on clarifying the mechanisms of the microstructure influencing the acid corrosion and mechanical characteristics of the as-sprayed NiCrBSi coating and post-heat-treated coating. The formation mechanisms of the amorphous phase of flat particles during the plasma spray process were studied by using X-ray diffraction analysis, Raman spectroscopy and confocal laser scanning microscope at first. Then the evolutionary process of the corrosion structure and phase of the coating in the accelerated corrosion experiment is directly visualized by using scanning electron microscopy and energy spectrum analysis. The mechanical properties of the amorphous NiCrBSi coatings are lastly measured by microhardness and friction wear tests. The critical phenomena and results help to elucidate the relative influence of the surface features of atmospheric plasma sprayed coatings on acid corrosion responses and wear resistance, aiming at contributing to the development of a protective technique for electrical engineering.

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Fabrication and Ablation Behavior of Plasma Sprayed ZrC-W Composite Coatings

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.602-603.552 ◽

2014 ◽

Vol 602-603 ◽

pp. 552-555

Author(s):

Dan Lu ◽

Ya Ran Niu ◽

Xue Lian Ge ◽

Xue Bing Zheng ◽

Guang Chen

Keyword(s):

Thermal Conductivity ◽

Thermal Shock ◽

Plasma Spray ◽

Composite Coatings ◽

Lamellar Microstructure ◽

Atmospheric Plasma Spray ◽

Atmospheric Plasma ◽

Plasma Flame ◽

Plasma Sprayed ◽

Zrc Coating

In this work, atmospheric plasma spray (APS) technology was applied to fabricate ZrC-W composite coatings. The microstructure of the composite coatings was characterized. The influence of W content on the ablation-resistant and thermal shock properties of ZrC-W composite coatings was evaluated using a plasma flame. The results show that the ZrC-W composite coatings had typically lamellar microstructure, which was mainly made up of cubic ZrC, cubic W and a small amount of tetragonal ZrO2. The ZrC-W coatings had improved ablation resistant and thermal shock properties compared with those of the pure ZrC coating. It was supposed that the improved density, thermal conductivity and toughness of the composite coatings contributed to this phenomenon.

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