Improve Stability of Dicalcium Silicate/Zirconia Composite Coatings by Post-Spraying Heat Treatment

The long-term stability of plasma-sprayed dicalcium silicate (C2S) composite coatings is determined by the phase composition, crystallinity, and other properties. Zirconia reinforcement and post-spraying heat treatment are applied to C2S coatings simultaneously in this work. The stability of the coating increases evidently by reinforcement with 70wt% zirconia and heat treatment at 800oC for 4 hours. SEM reveals that the smooth glassy surface of the as-sprayed coatings is replaced by randomly dispersed crystals. Tris-HCl immersion test results show that the dissolution rate of the composite coatings decreases after the heat treatment.

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TiC-TiSi2-Al2O3 composite coatings prepared by spray drying, heat treatment and plasma spraying

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2020.158221 ◽

2021 ◽

Vol 857 ◽

pp. 158221

Author(s):

Yu-duo Ma ◽

Wei Li ◽

Ming-yan Guo ◽

Yong Yang ◽

Yu-hang Cui ◽

...

Keyword(s):

Heat Treatment ◽

Spray Drying ◽

Plasma Spraying ◽

Composite Coatings ◽

Al2o3 Composite

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The Effect of Co-Deposition of SiC Sub-Micron Particles and Heat Treatment on Wear Behaviour of Ni–P Coatings

Coatings ◽

10.3390/coatings11020180 ◽

2021 ◽

Vol 11 (2) ◽

pp. 180

Author(s):

Donya Ahmadkhaniha ◽

Lucia Lattanzi ◽

Fabio Bonora ◽

Annalisa Fortini ◽

Mattia Merlin ◽

...

Keyword(s):

Heat Treatment ◽

Friction Coefficient ◽

Wear Mechanisms ◽

Composite Coatings ◽

Wear Behaviour ◽

Maximum Hardness ◽

Sic Particles ◽

Heat Treated ◽

The Coefficient Of Friction ◽

The Difference

The purpose of the study is to assess the influence of SiC particles and heat treatment on the wear behaviour of Ni–P coatings when in contact with a 100Cr6 steel. Addition of reinforcing particles and heat treatment are two common methods to increase Ni–P hardness. Ball-on-disc wear tests coupled with SEM investigations were used to compare as-plated and heat-treated coatings, both pure and composite ones, and to evaluate the wear mechanisms. In the as-plated coatings, the presence of SiC particles determined higher friction coefficient and wear rate than the pure Ni–P coatings, despite the limited increase in hardness, of about 15%. The effect of SiC particles was shown in combination with heat treatment. The maximum hardness in pure Ni–P coating was achieved by heating at 400 °C for 1 h while for composite coatings heating for 2 h at 360 °C was sufficient to obtain the maximum hardness. The difference between the friction coefficient of composite and pure coatings was disclosed by heating at 300 °C for 2 h. In other cases, the coefficient of friction (COF) stabilised at similar values. The wear mechanisms involved were mainly abrasion and tribo-oxidation, with the formation of lubricant Fe oxides produced at the counterpart.

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Preparation of Hydroxyapatite/Chitosan Biological Coatings on Carbon/Carbon Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.434-435.502 ◽

2010 ◽

Vol 434-435 ◽

pp. 502-505

Author(s):

Ying Hua Li ◽

Li Yun Cao ◽

Jian Feng Huang ◽

Xie Rong Zeng

Keyword(s):

Heat Treatment ◽

Electrophoretic Deposition ◽

Isopropyl Alcohol ◽

Raw Materials ◽

Composite Coatings ◽

Thermal Conditions ◽

Hydrothermal Condition ◽

Subsequent Heat Treatment ◽

Carbon Composites ◽

Deposition Voltage

Hydroxyapatite/Chitosan (HAp/CS) bio-coatings were prepared on the surface of carbon/ carbon (C/C) composites by hydrothermal electrophoretic deposition, using sonochemical process resulted HAp nanoparticles, isopropyl alcohol and chitosan as raw materials. The influences of hydro- thermal conditions and deposition voltage on the microstructures and morphologies of the as-prepared coatings were investigated. It was shown that homogenous and dense HAp/CS coatings on C/C composites are obtained by hydrothermal electrophoretic deposition. With the increase of deposition voltage, density and homogeneity of the as-prepared HAp/CS composite coatings are well improved. Due to the growth of HAp nanoparticles in the hydrothermal condition, the subsequent heat treatment of the HAp/CS coatings is not needed.

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Influence of the energy electron beam exposure regimes on the structure and mechanical properties of composite coatings

Izvestiya vysshikh uchebnykh zavedenii. Fizika ◽

10.17223/00213411/63/11/23 ◽

2020 ◽

pp. 23-27

Author(s):

T.A. Krylova ◽

◽

Y.A. Chumakov ◽

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Wear Resistance ◽

Electron Beam ◽

Structural Changes ◽

Composite Coatings ◽

Initial State ◽

Austenitic Structure ◽

Solid Carbide ◽

Soft Ferrite

The effect of heat treatment on the structure and properties of composite coatings based on chromium carbide with titanium carbide fabricated by non-vacuum electron beam cladding without has been studied. It was shown that tempering leads to a decrease in microhardness and wear resistance, which is associated with the decomposition of the austenitic structure with the formation of a soft ferrite-carbide structure. The post heat treatment tempering was showed to decrease of microhardness and wear resistance, which leads to the decomposition of the austenitic structure with the formation of a soft ferrite-carbide structure. The bulk quenching of coatings after tempering leads to an increase in microhardness comparable to the values of microhardness in the initial state after electron beam cladding, due to the formation of high hard martensite. The wear resistance of composite coatings after tempering is lower than after cladding due to brittle martensite, which is not able to hold solid carbide particles. The composite coatings obtained at the optimal processing conditions have a combination of improved properties and do not require additional heat treatment, resulting in structural changes, causing a decrease in mechanical properties.

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Effect of heat treatment temperature on the microstructure and wear corrosion properties of NiCrBSi–TiN composite coatings

Ceramics International ◽

10.1016/j.ceramint.2021.11.249 ◽

2021 ◽

Author(s):

YuXin Wang ◽

Jie Jiang ◽

YunLong Chi ◽

XingYe Mao ◽

LinLin Zhu ◽

...

Keyword(s):

Heat Treatment ◽

Heat Treatment Temperature ◽

Composite Coatings ◽

Treatment Temperature ◽

Corrosion Properties

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Tribological and Morphological Evaluation of Ni-P and Ni-P/D Coatings

Materials Science Forum ◽

10.4028/www.scientific.net/msf.969.73 ◽

2019 ◽

Vol 969 ◽

pp. 73-79

Author(s):

Bijoy Ramakrishnan ◽

K. Uday Venkat Kiran ◽

Pranit Rangari ◽

Anuj Prajapati ◽

Zuveria Firdouz ◽

...

Keyword(s):

Heat Treatment ◽

Steel Substrate ◽

Composite Coatings ◽

Surface Characteristics ◽

Dry Sliding Wear ◽

Diamond Coatings ◽

Morphological Evaluation ◽

Diamond Particles ◽

Aisi 52100 Steel ◽

P Matrix

The tribological characteristics of Electroless Ni-P and Ni-P/D (diamond) coatings were studied and analysed against AISI 52100 steel ball under dry reciprocating sliding conditions. Low and High Phosphorus Ni-P alloy coatings were deposited on steel substrate by Electroless deposition technique. Diamond particles were successfully reinforced into Ni-P matrix to produce Ni-P/D composite coatings. All coatings were subjected to heat treatment at 400°. The micro-hardness, surface features and elemental composition of the coatings was analysed. The surface morphology of Ni-P and Ni-P/D coatings is detailed. Presence of dia mond particles in Ni-P matrix was confirmed by EDS analysis. Dry sliding wear tests showed a significant enhancement in wear resistance of Ni-P/D composite coatings compared to Ni-P coatings. Experimental results indicate that combined effect of diamond particles reinforcement and heat treatment play a crucial role in modifying the surface characteristics and tribological performance of the Ni-P coatings.

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Electrodeposition of Co-B/SiC Composite Coatings: Characterization and Evaluation of Wear Volume and Hardness

Coatings ◽

10.3390/coatings9040279 ◽

2019 ◽

Vol 9 (4) ◽

pp. 279 ◽

Cited By ~ 2

Author(s):

A. Villa-Mondragón ◽

A. Martínez-Hernández ◽

F. Manríquez ◽

Y. Meas ◽

J. J. Pérez-Bueno ◽

...

Keyword(s):

Heat Treatment ◽

Composite Coatings ◽

Research Work ◽

Colloidal Suspensions ◽

Wear Volume ◽

X Ray Diffraction ◽

Homogeneous Composition ◽

Different Content ◽

Sic Coatings ◽

Hardness Values

In this research work, Co-B/SiC composite coatings were synthesized by electrochemical deposition from colloidal suspensions with different content of SiC. The Co-B/SiC films obtained were heat treatment at 350 °C. The composition, morphology, and structure of the Co-B/SiC composite coatings were analyzed using glow discharge spectrometry (GDS), scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Hardness and tribological properties were also studied. The results showed that an increase in the SiC concentration in the colloidal suspensions resulted in both an increase in the SiC content and a decrease in the B content in the obtained Co-B/SiC coatings. The Co-B/SiC coatings were adherent, glossy, and soft, and exhibited a homogeneous composition in all thicknesses. Besides, an increase in the SiC particle content of the Co-B/SiC composite coating from 0 to 2.56 at.% SiC reduced the hardness of the film from 680 to 360 HV and decreased the wear volume values from 1180 to 23 μm3 N−1 m−1, respectively (that is, the wear resistance increased). Moreover, when the Co-B/SiC coatings with SiC content ranging from 0 to 2.56 at.% SiC were subjected to a heat treatment process, the obtained coating hardness values were in the range of 1200 to 1500 HV, and the wear volume values were in the range of 382 to 19 μm3 N−1 m−1.

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