Material-efficient laser cladding for corrosion resistance

In order to improve the seawater corrosion resistance of Inconel 718 superalloy, a La2Zr2O7/NiCoCrAlY thermal barrier coating corrosion resistant to 3.5 wt.% NaCl aqueous solution was prepared by laser cladding on Inconel 718 superalloy. X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and electrochemical techniques were used to study the microstructure and the corrosion performance of the coating in 3.5 wt.% NaCl solution. The results show that the thermal barrier coating is mainly composed of primary La2Zr2O7 phase and γ + laves/δ phase eutectic structure. The corrosion potential and corrosion current of the coating in 3.5 wt.% NaCl solution are higher and lower than that of the Inconel 718 substrate, respectively, indicating that the corrosion performance of the coating is better than that of the Inconel 718 substrate. The presence of La2Zr2O7 phase in the thermal barrier coating is the main reason for its corrosion resistance to 3.5 wt.% NaCl solution.

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Wear and Corrosion Behaviours of FeCrNiSi Alloy Coatings by Laser Cladding

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.1406 ◽

2017 ◽

Vol 898 ◽

pp. 1406-1413

Author(s):

Yu Long Qi ◽

Hai Yan Chen ◽

Chen Yang Shu ◽

Xuan Zhao ◽

Li Hua Dong ◽

...

Keyword(s):

Corrosion Resistance ◽

Abrasive Wear ◽

Laser Cladding ◽

Wear Behavior ◽

Testing Machine ◽

Three Dimensional ◽

Xrd Analysis ◽

Hard Coating ◽

Wear Testing ◽

Surface Mapping

Soft and hard FeCrNiSi alloy coatings were obtained on 30CrMo alloy steel surface by laser cladding. The phase constitution, microstructure, frictional wear behavior and corrosion resistance of the composite coating were analyzed using X-ray diffraction (XRD), scanning electron microscope (SEM), three-dimensional non-contact surface mapping, friction and wear testing machine and electrochemical workstation, separately. XRD analysis showed that the cladding layer was mainly composed of Fe-based alloy composition, accompanied by a small amount of cobalt nickel alloy. There were massive protrusions in the interface of the soft sample, and the coating was regularly dendritic. Hard sample coating lines were cluttered, and there was no bulk deposition. Under the same wear condition, the soft coating exhibited serious abrasive wear, while the hard coating had slight abrasive wear behavior. The polarization curves in 3%NaCl solution revealed that the self-corrosion potential of the soft coating was positive shifted more than that the hard coating. The soft coating has better corrosion resistance than the hard coating.

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Optimization of laser cladding process for additive repair of high temperature and high pressure valve sealing surface

Materials Science Materials Review ◽

10.18063/msmr.v2i2.932 ◽

2019 ◽

Author(s):

Lei Che

Keyword(s):

High Pressure ◽

Corrosion Resistance ◽

High Temperature ◽

Laser Cladding ◽

Laser Power ◽

Feeding Rate ◽

Scanning Speed ◽

Alloy Layer ◽

Laser Cladding Process ◽

Valve Sealing

Laser cladding technology is highly suitable for the remanufacturing of thin-walled and easily deformable parts due to its concentrated energy density. Due to the high temperature and high pressure corrosion environment, the valve sealing surface is prone to corrosion, wear and other failures. A nickel-based tungsten carbide alloy layer was prepared on the valve sealing surface substrate material by laser cladding process. By designing orthogonal experiments, the effects of laser power (P), scanning speed (Vb), powder feeding rate (Vf), and WC content (wt%) on the alloy layer were investigated. A fuzzy comprehensive evaluation method including macroscopic quality, microstructure, microhardness, anti-wear performance, oxidation resistance, compactness and corrosion resistance was proposed. The experimental results showed that the hardness, oxidation resistance and corrosion resistance of the laser alloy layer are significantly improved compared with the matrix; the optimum process parameters and the addition ratio of WC powder are laser power (P) of 1.1 kW and scanning speed (Vb) of 800 mm/min. The powder feeding rate (Vf) was 20%, and the WC content was 20% by weight.

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Thermal Corrosion Resistance of Co-Based Alloy Coatings by Laser Cladding Assisted by Electromagnetic Stirring

Acta Optica Sinica ◽

10.3788/aos201939.0114002 ◽

2019 ◽

Vol 39 (1) ◽

pp. 0114002

Author(s):

徐家乐 Xu Jiale ◽

周建忠 Zhou Jianzhong ◽

谭文胜 Tan Wensheng ◽

黄舒 Huang Shu ◽

孟宪凯 Meng Xiankai ◽

...

Keyword(s):

Corrosion Resistance ◽

Laser Cladding ◽

Electromagnetic Stirring

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Microstructures and Corrosion Resistance Properties of Ni-Based WC/Cr3C2Coating Prepared by Laser Cladding

Laser & Optoelectronics Progress ◽

10.3788/lop48.091403 ◽

2011 ◽

Vol 48 (9) ◽

pp. 091403

Author(s):

薛敏鹏 Xue Minpeng ◽

韩彬 Han Bin ◽

王勇 Wang Yong ◽

刘兴光 Liu Xingguang

Keyword(s):

Corrosion Resistance ◽

Laser Cladding

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Effects of mass ratios on salt spray corrosion and electrochemical corrosion behaviors of laser cladded Cr–Ni coatings

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-10-2018-2015 ◽

2019 ◽

Vol 66 (3) ◽

pp. 352-359

Author(s):

Li Jiahong ◽

Kong Dejun

Keyword(s):

Corrosion Resistance ◽

Laser Cladding ◽

Salt Spray ◽

Electrochemical Corrosion ◽

Corrosion Mechanism ◽

H13 Steel ◽

Content Type ◽

Salt Spray Corrosion ◽

Electrochemical Tests ◽

Mass Ratios

Purpose The purpose of this paper is to improve the salt spray corrosion and electrochemical corrosion performances of H13 hot work mould steel, Cr–Ni coatings with the different Cr and Ni mass ratios are fabricated using a laser cladding (LC), which provides an experimental basis for the surface modification treatment of H13 steel. Design/methodology/approach Cr–Ni coatings with the different Cr and Ni mass ratios were firstly fabricated on H13 hot work mould steel using a laser cladding (LC). The salt spray corrosion (SSC) and electrochemical corrosion performances of Cr–Ni coatings in 3.5 Wt.% NaCl solution were investigated to analyze the corrosion mechanism, and the effect of mass ratios of Cr and Ni on their corrosion mechanism was discussed. Findings The laser cladded Cr–Ni coatings with the different Cr and Ni mass ratios are composed of Cr–Ni compounds, which are metallurgically combined with the substrate. The SSC resistance of Cr–Ni coating with the Cr and Ni mass ratios of 24:76 is the highest. The electrochemical corrosion resistance of Cr–Ni coating with the Cr and Ni mass ratio of 24:76 is the best among the three kinds of coatings. Originality/value In this study, the corrosion resistance of laser cladded Cr–Ni coatings with the Cr and Ni mass ratios of 17: 83, 20: 80 and 24: 76 was first evaluated using salt spray corrosion (SSC) and electrochemical tests, and the effect of mass ratios of Cr and Ni on their corrosion mechanism was discussed.

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