scholarly journals Microstructures and Properties of Laser Cladding Al-TiC-CeO2 Composite Coatings

Materials ◽  
2018 ◽  
Vol 11 (2) ◽  
pp. 198 ◽  
Author(s):  
Xing He ◽  
Dejun Kong ◽  
Renguo Song
Keyword(s):  
Laser Cladding ◽  
Composite Coatings

Laser cladding Ni-base composite coatings reinforced by in-situ synthesized multiple carbide particles

2008 ◽  
Author(s):  
Ruiquan Kang ◽  
Mingxing Ma ◽  
Wenjin Liu ◽  
Minlin Zhong ◽  
Yide Kan ◽  
...  
Keyword(s):  
Laser Cladding ◽  
Composite Coatings ◽  
Base Composite ◽  
Carbide Particles

scholarly journals Isothermal Oxidation Performance of Laser Cladding Assisted with Preheat (LCAP) Tribaloy T-800 Composite Coatings Deposited on EN8

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 843
Author(s):  
Sipiwe Trinity Nyadongo ◽  
Sisa Lesley Pityana ◽  
Eyitayo Olatunde Olakanmi
Keyword(s):  
Iron Oxide ◽  
Composite Coating ◽  
Laser Cladding ◽  
Composite Coatings ◽  
Parabolic Rate Constant ◽  
Mass Gain ◽  
Isothermal Oxidation ◽  
Operational Parameters ◽  
Temperature Oxidation ◽  
Service Environments

It is anticipated that laser cladding assisted with preheat (LCAP)-deposited Tribaloy (T-800) composite coatings enhances resistance to structural degradation upon exposure to elevated-temperature oxidation service environments. The oxidation kinetics of LCAP T-800 composite coatings deposited on EN8 substrate and its mechanisms have not been explored in severe conditions that are similar to operational parameters. The isothermal oxidation behaviour of the T-800 composite coating deposited on EN8 via LCAP was studied at 800 °C in air for up to 120 h (5 × 24 h cycles) and contrasted to that of uncoated samples. The mass gain per unit area of the coating was eight times less than that of the uncoated EN8 substrate. The parabolic rate constant (Kp) for EN8 was 6.72 × 10−12 g2·cm−4·s−1, whilst that for the T-800 composite coating was 8.1 × 10−13 g2·cm−4·s−1. This was attributed to a stable chromium oxide (Cr2O3) layer that formed on the coating surface, thereby preventing further oxidation, whilst the iron oxide film that formed on the EN8 substrate allowed the permeation of the oxygen ions into the oxide. The iron oxide (Fe2O3) film that developed on EN8 spalled, as evidenced by the cracking of oxide when the oxidation time was greater than 72 h, whilst the Cr2O3 film maintained its integrity up to 120 h. A parabolic law was observed by the T-800 composite coating, whilst a paralinear law was reported for EN8 at 800 °C up to 120 h. This coating can be used in turbine parts where temperatures are <800 °C.

Phase transformation and tribological properties of Ag-MoO 3 contained NiCrAlY based composite coatings fabricated by laser cladding

2017 ◽  
Vol 93 ◽  
pp. 79-86 ◽  
Author(s):  
Lingqian Wang ◽  
Jiansong Zhou ◽  
Benbin Xin ◽  
Youjun Yu ◽  
Shufang Ren ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Laser Cladding ◽  
Tribological Properties ◽  
Composite Coatings

scholarly journals Laser Cladding of Ni-Co-W Composite Coating on Stainless Steel to Enhance Wear Resistance

2021 ◽  
Author(s):  
Linlin ZHANG ◽  
Dawei ZHANG
Keyword(s):  
Stainless Steel ◽  
Wear Resistance ◽  
Composite Coating ◽  
Laser Cladding ◽  
Composite Coatings ◽  
Eutectic Structure ◽  
Wear Properties ◽  
Fine Grained ◽  
Noticeable Improvement ◽  
Enhance Wear Resistance

Ni-Co-W composite coatings modified by different contents of Co-based alloy powder in the Ni-based alloy with 35 wt.% WC (Ni35WC) were deposited on stainless steel by laser cladding. The influence of compositional and microstructural modification on the wear properties has been comparatively investigated by XRD, SEM, and EDS techniques. It was found that the austenite dendrites in the modified coating adding 50 wt.% Co-based alloy were refined and a lot of Cr23C6 or M23(C, B)6 compounds with fine lamellar feature were formed around austenitic grain boundaries or in the intergranular regions. The contribution of element Co to the modification of Ni35WC coating is that it cannot only promote the formation of more hard compounds to refine austenite grains, but also refine the size of precipitates, and change the phase type of eutectic structure as a result of disappeared Cr boride brittle phases. A noticeable improvement in wear resistance is obtained in the Ni35WC coating with 50 wt.% Co-based alloy, which makes the wear rate decreased by about 53 % and 30% by comparison to that of the substrate and the Ni35WC coating, respectively. It is suggested that the improvement is closely related to the composite coating being strengthened owing to the increase of coating hardness, formation of a fine-grained microstructure caused by Co, and fine hard precipitate phases in the eutectic structure.

scholarly journals Optimization of Ni-Based WC/Co/Cr Composite Coatings Produced by Multilayer Laser Cladding

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Andrea Angelastro ◽  
Sabina L. Campanelli ◽  
Giuseppe Casalino ◽  
Antonio D. Ludovico
Keyword(s):  
Laser Cladding ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Metallic Matrix ◽  
Optimization Procedure ◽  
High Hardness ◽  
Fatigue Properties ◽  
Metal Composite ◽  
Tungsten Carbides ◽  
Cobalt Chromium

As a surface coating technique, laser cladding (LC) has been developed for improving wear, corrosion, and fatigue properties of mechanical components. The main advantage of this process is the capability of introducing hard particles such as SiC, TiC, and WC as reinforcements in the metallic matrix such as Ni-based alloy, Co-based alloy, and Fe-based alloy to form ceramic-metal composite coatings, which have very high hardness and good wear resistance. In this paper, Ni-based alloy (Colmonoy 227-F) and Tungsten Carbides/Cobalt/Chromium (WC/Co/Cr) composite coatings were fabricated by the multilayer laser cladding technique (MLC). An optimization procedure was implemented to obtain the combination of process parameters that minimizes the porosity and produces good adhesion to a stainless steel substrate. The optimization procedure was worked out with a mathematical model that was supported by an experimental analysis, which studied the shape of the clad track generated by melting coaxially fed powders with a laser. Microstructural and microhardness analysis completed the set of test performed on the coatings.

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