Effect of Ni Addition on In Situ WC-Cr3C2 Cermet Coating by Laser Controlled Reactive Synthesisuse

WC-Cr3C2 cermet coating on carbon steel was fabricated by laser controlled reactive synthesis and exhibited the metallurgical bonding at the interface between coating and substrate. Experimental results show that addition of Ni results in a significant change on phases and microstructure of coating. Ni addition remarkable improves resistance to thermal shock of coating. This is accounted for by increasing planar crystal zone of the coating due to Ni addition, which decreases stress concentration at the interface.

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Fabrication of TiC Coating on Carbon Steel Surface by SHS/PHIP

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1304 ◽

2008 ◽

Vol 368-372 ◽

pp. 1304-1306

Author(s):

Hong Zhao ◽

Xing Hong Zhang

Keyword(s):

Carbon Steel ◽

Thermal Shock ◽

Combustion Synthesis ◽

Bonding Strength ◽

Thermal Shock Resistance ◽

Steel Surface ◽

Metallurgical Bonding ◽

Carbon Steel Surface ◽

Distribution Of Elements ◽

Shock Resistance

A TiC coating was fabricated on a carbon steel surface by SHS/PHIP (combustion synthesis/pseudo heat isostatic pressing) process. Phases in the coating were determined by XRD. We employ SEM-EDS to analyze the microstructure of the coating and bonding interface between the substrate and the coating, and the distribution of elements adjacent to the interface. The microhardness of the coating was also measured. Our results showed that the coating was composed of TiC and Fe phases, with dense and pure microstructure. Metallurgical bonding was formed between the substrate and coating. The result of thermal shock resistance test showed that the coating has good bonding strength and hardness of the coating was four times higher than that of the substrate.

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Cladding of WC-Cr3C2 Cermet Coating by Laser Controlled Reactive Synthesis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1872 ◽

2008 ◽

Vol 368-372 ◽

pp. 1872-1875 ◽

Cited By ~ 4

Author(s):

Wen Ge Li ◽

Guang Jun Zhang ◽

Jun Li

Keyword(s):

Phase Composition ◽

Synthesis Method ◽

Phase System ◽

Interface Morphology ◽

Complex Phase ◽

Reactive Synthesis ◽

Cermet Coating ◽

Method Effect ◽

Metallurgical Bonding ◽

Key Factor

WC-Cr3C2 cermet coating on carbon steel was fabricated by laser controlled reactive synthesis method. Effect of diluents is the key factor influencing the cladding process. When the amount of diluents is 30%, the reaction becomes steadily and the smooth coating can be achieved. Observations of the microstructure and phase composition of the sample showed that the coating was a complex phase system which consisted of WC and Cr3C2. In order to improve bond strength of the coating, Ni was selected as additive. The interface morphology showed that the bonding between coating and substrate was metallurgical bonding.

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Promoting Hydrogen Evolution of g-C3N4 Based Photocatalyst by Indium and Phosphorus Co-doping

New Journal of Chemistry ◽

10.1039/d1nj00585e ◽

2021 ◽

Author(s):

Xiao-Hang Yang ◽

Chi Cao ◽

Zilong Guo ◽

Xiaoyu Zhang ◽

Yaxin Wang ◽

...

Keyword(s):

Hydrogen Evolution ◽

Post Treatment ◽

Experimental Results ◽

Indium Chloride ◽

Co Doping ◽

In Situ Copolymerization ◽

Co Doped

Indium and phosphorus co-doped g-C3N4 photocatalyst (In,P-g-C3N4) was prepared by K2HPO4 post-treatment of indium doped g-C3N4 photocatalyst (In-g-C3N4) derived from in-situ copolymerization of dicyandiamide and indium chloride. The experimental results...

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Phase Transition and Coefficients of Thermal Expansion in Al2−xInxW3O12 (0.2 ≤ x ≤ 1)

Materials ◽

10.3390/ma14144021 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4021

Author(s):

Andrés Esteban Cerón Cerón Cortés ◽

Anja Dosen ◽

Victoria L. Blair ◽

Michel B. Johnson ◽

Mary Anne White ◽

...

Keyword(s):

Phase Transition ◽

Thermal Expansion ◽

Thermal Shock ◽

Monoclinic Phase ◽

Ceramic Materials ◽

Precipitation Method ◽

Scanning Calorimetry ◽

Orthorhombic Crystal ◽

Co Precipitation

Materials from theA2M3O12 family are known for their extensive chemical versatility while preserving the polyhedral-corner-shared orthorhombic crystal system, as well as for their consequent unusual thermal expansion, varying from negative and near-zero to slightly positive. The rarest are near-zero thermal expansion materials, which are of paramount importance in thermal shock resistance applications. Ceramic materials with chemistry Al2−xInxW3O12 (x = 0.2–1.0) were synthesized using a modified reverse-strike co-precipitation method and prepared into solid specimens using traditional ceramic sintering. The resulting materials were characterized by X-ray powder diffraction (ambient and in situ high temperatures), differential scanning calorimetry and dilatometry to delineate thermal expansion, phase transitions and crystal structures. It was found that the x = 0.2 composition had the lowest thermal expansion, 1.88 × 10−6 K−1, which was still higher than the end member Al2W3O12 for the chemical series. Furthermore, the AlInW3O12 was monoclinic phase at room temperature and transformed to the orthorhombic form at ca. 200 °C, in contrast with previous reports. Interestingly, the x = 0.2, x = 0.4 and x = 0.7 materials did not exhibit the expected orthorhombic-to-monoclinic phase transition as observed for the other compositions, and hence did not follow the expected Vegard-like relationship associated with the electronegativity rule. Overall, compositions within the Al2−xInxW3O12 family should not be considered candidates for high thermal shock applications that would require near-zero thermal expansion properties.

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The high enrichment of Geobacter by TiN nanoarray anode catalyst for efficient microbial fuel cells

Journal of Materials Chemistry A ◽

10.1039/d0ta11788a ◽

2021 ◽

Vol 9 (12) ◽

pp. 7726-7735

Author(s):

Da Liu ◽

Weicheng Huang ◽

Qinghuan Chang ◽

Lu Zhang ◽

Ruiwen Wang ◽

...

Keyword(s):

Fuel Cells ◽

Hierarchical Structure ◽

Microbial Fuel Cells ◽

Dft Calculation ◽

Experimental Results ◽

Carbon Cloth ◽

Anode Catalyst ◽

High Enrichment

TiN nanoarrays, in situ grown on carbon cloth gather 97.2% of the model exoelectrogen Geobacter, greatly enhancing the MFCs' performance. The experimental results and DFT calculation certify the importance of the micro–nano-hierarchical structure.

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Design an Epoxy Coating with TiO2/GO/PANI Nanocomposites for Enhancing Corrosion Resistance of Q235 Carbon Steel

Materials ◽

10.3390/ma14102629 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2629

Author(s):

Shimin Chen ◽

Bo Li ◽

Rengui Xiao ◽

Huanhu Luo ◽

Siwu Yu ◽

...

Keyword(s):

Carbon Steel ◽

Photocurrent Density ◽

Photoelectrochemical Performance ◽

Q235 Steel ◽

Protective Barrier ◽

Barrier Coating ◽

Pani Composite ◽

Steel Protection ◽

Q235 Carbon Steel

In this work, a ternary TiO2/Graphene oxide/Polyaniline (TiO2/GO/PANI) nanocomposite was synthesized by in situ oxidation and use as a filler on epoxy resin (TiO2/GO/PANI/EP), a bifunctional in situ protective coating has been developed and reinforced the Q235 carbon steel protection against corrosion. The structure and optical properties of the obtained composites are characterized by XRD, FTIR, and UV–vis. Compared to bare TiO2 and bare Q235, the TiO2/GO/PANI/EP coating exhibited prominent photoelectrochemical properties, such as the photocurrent density increased 0.06 A/cm2 and the corrosion potential shifted from −651 mV to −851 mV, respectively. The results show that the TiO2/GO/PANI nanocomposite has an extended light absorption range and the effective separation of electron-hole pairs improves the photoelectrochemical performance, and also provides cathodic protection to Q235 steel under dark conditions. The TiO2/GO/PANI/EP coating can isolate the Q235 steel from the external corrosive environment, and may generally be regarded a useful protective barrier coating to metallic materials. When the TiO2/GO/PANI composite is dispersed in the EP, the compactness of the coating is improved and the protective barrier effect is enhanced.

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Experimental Theoretical Studies on Extract of Date Palm Seed as a Green Anti-Corrosion Agent in Hydrochloric Acid Solution

Molecules ◽

10.3390/molecules26123535 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3535

Author(s):

Naba Jasim Mohammed ◽

Norinsan Kamil Othman ◽

Mohamad Fariz Mohamad Taib ◽

Mohd Hazrie Samat ◽

Solhan Yahya

Keyword(s):

Carbon Steel ◽

Hydrochloric Acid ◽

Active Sites ◽

Immersion Time ◽

Steel Surface ◽

Date Palm ◽

Inhibition Efficiency ◽

Experimental Results ◽

Plant Materials ◽

Carbon Steel Surface

Extracts from plant materials have great potential as alternatives to inorganic corrosion inhibitors, which typically have harmful consequences. Experimental and theoretical methodologies studied the effectiveness of agricultural waste, namely, date palm seed extract as a green anti-corrosive agent in 0.5 M hydrochloric acid. Experimental results showed that immersion time and temperature are closely related to the effectivity of date palm seed as a corrosion inhibitor. The inhibition efficiency reduced from 95% to 91% at 1400 ppm when the immersion time was increased from 72 h to 168 h. The experimental results also indicated that the inhibition efficiency decreased as the temperature increased. The presence of a protective layer of organic matter was corroborated by scanning electron microscopy. The adsorption studies indicated that date palm seed obeyed Langmuir adsorption isotherm on the carbon steel surface, and Gibbs free energy values were in the range of −33.45 to −38.41 kJ·mol−1. These results suggested that the date palm seed molecules interacted with the carbon steel surface through mixture adsorption. Theoretical calculations using density functional theory showed that the capability to donate and accept electrons between the alloy surface and the date palm seed inhibitor molecules is critical for adsorption effectiveness. The HOMO and LUMO result indicated that the carboxyl (COOH) group and C=C bond were the most active sites for the electron donation-acceptance type of interaction and most auxiliary to the adsorption process over the Fe surface.

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