Journal articles: 'Ni-Ni3B'

1

Azhazha, V. M., V. E. Semenenko, and N. N. Pilipenko. "Ni-Ni3B composite coating." Powder Metallurgy and Metal Ceramics 46, no. 1-2 (January 2007): 32–37. http://dx.doi.org/10.1007/s11106-007-0006-8.

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Xu, Jun Feng, Feng Liu, Man Zhu, and Zeng Yun Jian. "Differential Scanning Calorimetry Studies on Ni-Ni₃B Alloys." Materials Science Forum 817 (April 2015): 556–59. http://dx.doi.org/10.4028/www.scientific.net/msf.817.556.

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Solidification behaviors of hypoeutectic Ni-3.3wt% B and hypereutectic Ni-4.5wt% B alloys were investigated by using differential scanning calorimetry (DSC) technology. Experimental results showed that the solidification behaviors are similar for the two kinds of alloys with small sizes, i.e. three transformed peaks (corresponding to L→α-Ni, L→Ni-Ni23B6and Ni23B6→Ni+Ni3B, respectively) appear in the cooling curves, and three phases (primary phase α-Ni, rod eutectic and dot precipitates) appear in the microstructures, which are different from that of the alloys with large sizes. It can be attributed to the fact that the nucleation of α-Ni and Ni23B6phases are easier than that of Ni3B phase for small samples of hypoeutectic and hypereutectic Ni-Ni3B alloys.

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3

Kim, Yong Hwan, Il Ho Kim, K. T. Kim, Seung Y. Shin, and S. I. Kwun. "Identification of Phases in the Wide-Gap Region Brazed with BNi-3 Filler Metal Powder Using Electron Backscatter Diffraction." Materials Science Forum 544-545 (May 2007): 355–58. http://dx.doi.org/10.4028/www.scientific.net/msf.544-545.355.

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The phases formed in the wide-gap region brazed with BNi-3 filler metal powder in IN738 superalloy were investigated by electron backscatter diffraction (EBSD). The morphology and chemical composition of the phase were investigated by field emission scanning electron microscopy (FESEM) and Auger electron spectroscopy (AES). The wide-gap region brazed with BNi-3 filler metal had a microstructure consisting of primary Ni3B, binary eutectic of Ni3B-Ni solid solution and ternary eutectic of Ni3B-Ni-Ni3Si structure. EBSD pattern analysis revealed that the Ni3B had orthorhombic structure with lattice parameter of a=0.439, b=0.522 and c=0.662 nm, and the Ni3Si phase had cubic structure with lattice parameter of a=0.350 nm.

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Kim, Yong Hwan, and S. I. Kwun. "Changes in Mechanical Properties of the Wide-Gap Region Brazed with Various Brazing Temperatures and Times." Materials Science Forum 486-487 (June 2005): 113–16. http://dx.doi.org/10.4028/www.scientific.net/msf.486-487.113.

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The microstructural changes and the relations between mechanical properties and additive powder with various brazing temperatures and times were investigated. The IN738 and BNi-3 alloy powders were used as an additive and filler metal powders for the brazing process. The wide-gap brazing process was carried out in a vacuum of 2×10-5 torr. The wide-gap region brazed with 60wt.% IN738 additive powder had a microstructure consisting of IN738 additive, and binary eutectic of Ni3B-Ni, and (Cr, W)B. As the brazing temperature and time were increased, the size of IN738 additive powder increased to 181µm, which decreased the amount of low strength Ni3B-Ni eutectic structure, thereby increasing the fracture strength of the wide-gap brazed region. Cracks in the brazed region were observed to propagate through the Ni3B-Ni structure, which lowered the fracture strength of the wide-gap brazed region.

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Kim, Yong Hwan, Ki Tae Kim, and Il Ho Kim. "Effect of Mixing Ratio on Mechanical Properties of Wide-Gap Brazed Ni-Based Superalloy with Ni-Si-B Alloy Powder." Key Engineering Materials 306-308 (March 2006): 935–40. http://dx.doi.org/10.4028/www.scientific.net/kem.306-308.935.

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This study investigated the microstructure and mechanical properties of a wide-gap region brazed with various powders mixing ratios of additive powder to filler metal powder. The IN738 and BNi-3 alloy powders were used as additive and filler metal powder for the brazing process. The wide-gap brazing process was carried out in a vacuum of 2×10-5 torr. It was observed that the region brazed with only filler metal had a microstructure consisting of fully eutectic and dendrite structures. However, the region brazed with 60wt.% IN738 additive powder consisted of IN738 additive, Ni3B-Ni eutectic and (Cr, W)B. The fracture strength of the wide-gap region (70 wt.% additive and 30 wt.% filler metal powder) was as high as 687 MPa at room temperature. The Cracks in the wide-gap brazed region initiated at the Ni3B-Ni eutectic and (Cr, W)B, and then propagated through them. It was found that the Ni3B-Ni eutectic and (Cr, W)B in the brazed region are important microstructural factors affecting the mechanical properties of the wide-gap brazed region.

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Pal, Soupitak, Vikram Jayaram, Sanjay Kumar Biswas, and Yancy Riddle. "Effect of Phases on the Frictional Properties of Electroless Ni-B Nano-Composite Coating." Advances in Science and Technology 66 (October 2010): 120–25. http://dx.doi.org/10.4028/www.scientific.net/ast.66.120.

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As-deposited amorphous (determined through XRD) electroless Ni-B coating upon heat treatment transforms to crystalline phases, Ni3B, Ni2B and Ni whose volume fractions can vary widely. A micro and nano tribological study through ball-on-disk tribometer and lateral force microscopy has been performed to understand the effect of phase mixture (Ni3B +Ni2B) on the frictional properties of this coating. Though scaling of the contact area from micro to nano level strongly influences the friction coefficient, it has also been found that increase in the Ni2B:Ni3B ratio of the crystalline coating reduces the friction coefficient significantly.

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7

Kornienko, Elena, Aelita Nikulina, Ekaterina Drobyaz, Natalya V. Plotnikova, Elizaveta Lapushkina, and Victor Kuz'min. "The Effect of Heat Temperature on the Structure of Plasma Coating of the Ni-Cr-Si-B System." Applied Mechanics and Materials 788 (August 2015): 252–58. http://dx.doi.org/10.4028/www.scientific.net/amm.788.252.

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The powder of the Ni-Cr-Si-B system was applied on tubes of low carbon steel (0.2 % C) with the help of air-plasma spraying. The effect of heating temperature on the microstructure of obtained coatings was analyzed in this paper. The coatings were heated up to 500, 600, 700, 800, 900, 1000, and 1100 °C and cooled in the air. It was shown by the method of optical and scanning electron microscopy (SEM) and the X-ray diffraction analysis (XRD) that the same phases (γ-Ni, Ni3B, Ni3Si and Cr2B) were present in the coatings before and after heating. Chromium carbide Cr7C3 was observed in the coating structure after heating to above 1000 °C. Coatings which were heated to 1000 °C consisted of grains of the solid nickel base solution, micro volumes of the Ni+Ni3Si eutectic with inclusions of Ni3B and particles of Cr7C3. The coatings which were crystallized from a liquid state (heated up to 1100 °C) consisted of large areas of the solid nickel base solution and particles of chromium carbide Cr7C3. The space between nickel areas is filled by the Ni3Si+Ni3B eutectic.

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8

Shahbazi, Mahboobeh, Henrietta Cathey, Natalia Danilova, and Ian Mackinnon. "Single Step Process for Crystalline Ni-B Compounds." Materials 11, no. 7 (July 22, 2018): 1259. http://dx.doi.org/10.3390/ma11071259.

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Crystalline Ni2B, Ni3B, and Ni4B3 are synthesized by a single-step method using autogenous pressure from the reaction of NaBH4 and Ni precursors. The effect of reaction temperature, pressure, time, and starting materials on the composition of synthesized products, particle morphologies, and magnetic properties is demonstrated. High yields of Ni2B (>98%) are achieved at 2.3–3.4 MPa and ~670 °C over five hours. Crystalline Ni3B or Ni4B3 form in conjunction with Ni2B at higher temperature or higher autogenous pressure in proportions influenced by the ratios of initial reactants. For the same starting ratios of reactants, a longer reaction time or higher pressure shifts equilibria to lower yields of Ni2B. Using this approach, yields of ~88% Ni4B3 (single phase orthorhombic) and ~72% Ni3B are obtained for conditions 1.9 MPa < Pmax < 4.9 MPa and 670 °C < Tmax < 725 °C. Gas-solid reaction is the dominant transformation mechanism that results in formation of Ni2B at lower temperatures than conventional solid-state methods.

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9

Kim, Yong Hwan, and S. I. Kwun. "Phase Analysis in the Region Brazed with Ni-14Cr-10Co-3.5Al-2.5Ta-2.8B Filler Metal Using Electron Backscatter Diffraction." Materials Science Forum 569 (January 2008): 93–96. http://dx.doi.org/10.4028/www.scientific.net/msf.569.93.

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The phases formed in the wide-gap region brazed with Ni-14Cr-10Co-3.5Al-2.5Ta-2.8B filler metal powder in IN738 superalloy were investigated by electron backscatter diffraction (EBSD). The wide-gap brazing process was carried out in a vacuum of 2×10-5 torr at 1503 K. The region brazed with filler metal powders had a microstructure consisting of two kinds of eutectic colonies, one is Ni solid solution-CrB eutectic and the other is Ni solid solution-Ni3B eutectic. EBSD pattern analysis revealed that the CrB phase had orthorhombic structure with lattice parameters of a=0.297, b=0.786 and c=0.293 nm, and the Ni3B phase had orthorhombic structure with lattice parameters of a=0.439, b=0.522 and c=0.662 nm. The cuboidal-shaped phase precipitated in the Ni solid solution was found to be the γ' (Ni3Al) phase, which had cubic structure with lattice parameter of a=0.357 nm.

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10

Liu, Feng, Junfeng Xu, Di Zhang, and Zengyun Jian. "Solidification of Highly Undercooled Hypereutectic Ni-Ni3B Alloy Melt." Metallurgical and Materials Transactions A 45, no. 11 (July 22, 2014): 4810–19. http://dx.doi.org/10.1007/s11661-014-2460-5.

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11

Wang, Qian, Qian Li, Fa Qiang Chen, Liang Zhang, Ji Dong Li, and Jun Wei Zhang. "Corrosion behavior of laser-cladding NiCrBSi coating in molten aluminum alloy." Journal of Laser Applications 34, no. 2 (May 2022): 022022. http://dx.doi.org/10.2351/7.0000465.

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In order to investigate the corrosion mechanism in molten aluminum alloy, NiCrBSi coating was prepared on H13 tool steel by laser-cladding. The coating mainly contained γ-(Ni, Fe), Cr7C3, Ni3B, and CrB. Floret-shaped CrB and dendritic Cr7C3 were uniformly distributed in the Ni-based solid solution matrix, with Ni-Ni3B network eutectics separated around them. The corrosion test results in molten aluminum alloy at 1073 K revealed that NiCrBSi coating exhibited excellent corrosion resistance, which was attributed to its boride-containing phase composition and microstructure. Borides can help prevent the coating surface from being wetted by liquid aluminum at the early stage of corrosion. With the prolongation of the corrosion time, molten aluminum alloy began to wet the coating surface and react with it to form a transition layer. However, the dense network structure formed by CrB hard phases and boron-rich eutectics can effectively prevent liquid aluminum from intruding into the interior part of the coating. Meanwhile, the raised borides at the interface can also slow down the reaction between aluminum and the surrounding Ni-based matrix. Thus, the corrosion rate was relatively slow and a transition layer with the thickness of 140 μm was formed after 150 h of corrosion, while the inferior coating and H13 substrate still remained intact.

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12

Gladys, Armin, Michael Brohl, Friedhelm Schlawne, and Helmut Alexander. "Eigenschaften des eutektischen Teilsystems Ni - Ni3B, erschlossen aus magnetischen Messungen." International Journal of Materials Research 76, no. 4 (April 1, 1985): 254–56. http://dx.doi.org/10.1515/ijmr-1985-760404.

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13

Liu, Feng, and Jun Feng Xu. "Undercooled Solidification of Ni-3.3wt.%B Alloy." Advanced Materials Research 562-564 (August 2012): 15–18. http://dx.doi.org/10.4028/www.scientific.net/amr.562-564.15.

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Ni-3.3wt.%B alloy solidified at different undercooling by glass fluxing has been studied. The as-solidified structure is mainly controlled by the undercooling for eutectic solidification, ΔT2, instead of ΔT1, the undercooling for primary solidification. For ∆T22 ≥145±5K, three recalescence peaks appear in cooling curves. If ∆T22≥145±5 K, two kinds of dot phases occur. Further analysis declares that, the regularly distributed dot phases with larger size come from the transformation L→Ni23B6+Ni, whereas, the irregularly distributed ones with smaller size come from Ni23B6→Ni3B+Ni. Both of them have a contribution to strengthen the mechanical property.

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14

Skulev, Hristo, and Deyan Veselinov. "The Influence of Substrate Materials on the Microstructure, Microhardness and Wear Resistance of Nickel-base Plasma Spray Coatings." Proceedings of the Bulgarian Academy of Sciences 75, no. 9 (September 30, 2022): 1343–50. http://dx.doi.org/10.7546/crabs.2022.09.12.

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This paper studies the influence of the substrate material on the phase composition, microstructure, microhardness, and wear resistance of Ni-Cr-BSi-WC (Ni95Al5) coatings. Three types of substrates were studied, AISI 5060 Steel, SAE J431 automotive gray cast iron, and Ti-6Al-4V. It has been found that in the as-coated condition the surface layers have a phase composition of crystalline ɣ-Ni solid solution, amorphous, Ni3B, CrB, and Cr23C6. There are different changes of the surface after 80 min abrasive wheel.

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15

Khoma, M., R. Mardarevych, V. Vynar, Сh Vasyliv, and Yu Kovalchyk. "Influence of heat treatment on tribocorrosion properties of Ni-B composite coatings." Problems of Tribology 27, no. 1/103 (March 27, 2022): 34–40. http://dx.doi.org/10.31891/2079-1372-2022-103-1-34-40.

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Various surface protection technologies, in particular, electrochemical, are used to increase the wear and corrosion resistance of steels and alloys. Composite electrochemical coatings (CEC) technology is more promising than "pure" galvanic coatings. Application of CEC increases the wear, corrosion and fatigue failure resistance of metals. Nickel often is chosen as a CEC matrix because it easily forms uniformly filled defect-free composite structures with many particles of the dispersed phase (DP). Physical and mechanical properties of metal coatings determine practical application of such composition. The characteristics of nickel-based CEC are: high hardness and strength, significant corrosion resistance in atmospheric environment, as well as in alkali and mild acidy environments. An effective composition coating with tribological designation can be CEC Ni-B, received in the process of electrolysis from suspension of amorphous boron in nickel electrolyte. A new composite structure of matrix filled type Ni-Ni3B is formed after heat treatment. Composition and structure of coating is determined by regimes of diffusion annealing. Ni-B coatings increase wear resistance of steel in chlorine-based environments. The influence of low-temperature thermal treatment of Ni-B CEC on steel 09Mn2Si on their tribocorrosion behavior is investigated. It is shown that the structural factor has a decisive influence on the efficiency of such friction pairs. The CEC has the least wear and the most positive compromise electrode potential after vacuum annealing at 450°C, when the initial stage of solid-phase interaction of coating components with the formation of Ni-Ni3B occurs.

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16

Saito, Tetsuji, Hironori Sato, and Tetsuichi Motegi. "Extraction of Rare Earth from La–Ni Alloys by the Glass Slag Method." Journal of Materials Research 18, no. 12 (December 2003): 2814–19. http://dx.doi.org/10.1557/jmr.2003.0392.

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The use of the glass slag method in the extraction of rare earth from La–Ni alloys was studied. X-ray diffraction and electron probe microanalysis studies revealed that the La–Ni alloys produced by the glass slag method using boron trioxide consisted of Ni and Ni3B phases. No La-containing phase such as the LaNi5 phase and the La oxide phase was found in the resultant alloys. The chemical analyses confirmed that the La content in the alloys produced by the glass slag method was very limited. However, the glass slag materials contained a large amount of lanthanum. The La in the La–Ni alloys was successfully extracted by the glass slag method using boron trioxide.

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17

Guo, Jie, Yongjiang Hou, Bo Li, and Yaquan Wang. "Ni3B–Ni nanocomposites for improved electrocatalytic activity in methanol oxidation reaction." Journal of Applied Electrochemistry 46, no. 12 (August 27, 2016): 1177–86. http://dx.doi.org/10.1007/s10800-016-1000-y.

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18

Chen, Chuan Hui, Yang Bai, Wei Chen, and Xu Chu Ye. "Boron Influence on Structures and Properties in Nickel-Based Alloys." Applied Mechanics and Materials 395-396 (September 2013): 251–58. http://dx.doi.org/10.4028/www.scientific.net/amm.395-396.251.

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Nickel-base alloys with different boron contents were prepared by vacuum arc furnace. The effect of the boron contents to metallography was characterized simultaneously by XRD and SEM with EDS part. The thermal behavior was analyzed by DSC curves which mainly represents the eutectic temperature of alloys. The Vickers hardness and ball-on-flat wear test were carried out to reveal the relationship between metallographic phase formation and wear resistance. The results indicated that main composites are eutectic Ni-Cr as matrix and CrB, Ni3B as precipitated phase. A considerable amount of dislocation and stacking faults exist in the specific orientation (200) of Ni3B. 2.0~4.0%B alloys melt at 1060oC, while the boride-poor alloy melts at 1085oC. 3.0~4.0%B alloys performed the best on wear resistance. Wear volume reduces along with increasing hardness at the beginning, and then keeps invariant. Borides are main reinforcing phases, which affects hardness and wear resistance greatly.

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19

Hernández, Jorge Morales, José Manuel Juárez García, Héctor Herrera Hernández, Héctor J. Dorantes Rosales, and Raul Herrera Basurto. "Synthesis of TiB₂-Ni₃B nanocomposite coating by DC magnetron sputtering for corrosion-erosion protection." Materials Research Express 8, no. 12 (December 1, 2021): 126403. http://dx.doi.org/10.1088/2053-1591/ac3f0c.

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Abstract Significant contribution on corrosion-erosion resistance of Ni3B-TiB2 nanocomposite coating of 1 μm of thickness, deposited by DC magnetron Sputtering on stainless steel 304 substrates was studied. Nickel phase (γ Ni) plus Ni3B-TiB2 phases were synthesized previously by Mechanical Alloying (MA). Solid cathode (76.2 mm of diameter and 3 mm of thickness) used to grow thin films was manufactured with the alloyed powders, applying a uniaxial load of 70 MPa at room temperature and sintered at 900 °C for two hours. Microstructure and mechanical properties of the coatings were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), nanoindentation, and wear test with a ball-on-disc tribometer. Compact coating of Ni3B-TiB2 with a microstructure of prismatic crystals after annealing treatment, showing a uniform coating with good adherence and low friction coefficient of 0.5, correlated with a low roughness of Ra ≈ 0.0439 ± 0.0069 μm. The average hardness of 537.4 HV (5265.0 MPa) and wear coefficient at room temperature of 2.552E-10 m2N−1 correspond with medium-hard phases with an elastic-plastic behavior suitable for fatigue applications. Geothermal fluid modified was synthesized in the lab with NaCl/Na2SO4 to evaluate the corrosion resistance of the films in a standard three electrodes cell, characterizing a corrosion rate of 0.0008 and 0.001 mm*year−1 at 25 and 80 °C respectively during 86.4 ks (24 h) of exposition; showing a resistive coating without corrosion products and with good response to the geothermal environment.

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20

Xia, Cheng Bao, Ming Wu Tu, and Qing Jun Pan. "Performance and Property of Ni Base Coatings by Using Plasma Arc Technology for 18Cr2Ni4WA Steel Repairing." Advanced Materials Research 189-193 (February 2011): 311–15. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.311.

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To understand the structure and performance of Ni base coatings on 18Cr2Ni4WA steel, the key techniques of plasma arc cladding method are introduced. Microstructure and microhardness of the coating clad were analyzed by using Vickers hardness tester,scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).Results show that the phase of the coating is composed of γ-Ni solid solution， nickel boride Ni3B，carbide Cr27C6 and Cr2B3 type chromium boride. The coating has no cracks and does not exhibit porosity, the bonding between layers is compact and the boundaries are not observed. The coating is featured by a homogenized microstructure; small grain and no evident heat-affected zone.

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21

Xu, Junfeng, Feng Liu, and Di Zhang. "In situ observation of solidification of undercooled hypoeutectic Ni–Ni3B alloy melt." Journal of Materials Research 28, no. 14 (June 26, 2013): 1891–902. http://dx.doi.org/10.1557/jmr.2013.165.

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22

Kalidindi, Suresh Babu, Amit Ashok Vernekar, and Balaji R. Jagirdar. "Co–Co2B, Ni–Ni3B and Co–Ni–B nanocomposites catalyzed ammonia–borane methanolysis for hydrogen generation." Phys. Chem. Chem. Phys. 11, no. 5 (2009): 770–75. http://dx.doi.org/10.1039/b814216e.

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23

Ajao, J., and S. Hamar-Thibault. "Influence of additions on the solidification behaviour of Ni-B alloys ? crystallography of Ni-Ni3B eutectic." Journal of Materials Science 23, no. 3 (March 1988): 1112–25. http://dx.doi.org/10.1007/bf01154022.

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24

Skulev, Hristo, and Deyan Veselinov. "The Influence of Steel and Cast Iron as Substrate Materials on the Microstructure, Microhardness and Wear Resistance of Nickel-base Ti-Al Plasma Spray Coatings." Proceedings of the Bulgarian Academy of Sciences 75, no. 11 (November 30, 2022): 1656–62. http://dx.doi.org/10.7546/crabs.2022.11.13.

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This paper studies the influence of different substrate materials on the phase composition, microstructure, microhardness, and wear resistance of Ni-Cr-B-Si-C-Ti-Al plasma spray coatings. Two types of substrate metals were studied – AISI 1045 steel and Pig-P3 Si grey cast iron. It has been found that in the as-coated condition the surface layers have a phase composition of γ-Ni, Cr23C6, γ-TiAl, TiN, and α-Ti(N, O) on steel substrate, and γ-Ni, α-Ti, TiN, Ni3B, CrB, Cr23C6, α-Ti(N, O), Ni3Si on cast iron. The microhardness and wear resistance of the plasma sprayed Ni-Cr-B-Si-C-Ti-Al coatings is tested. The wear volume of the coatings has been tested for up to 60 min. The deposits on cast iron substrates demonstrate lower wear than those on the steel substrate.

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Yu, Jing, and Bo Song. "Microstructure and Properties of Ni-Based Alloy Coating with Ultrasonic Frequency Inductive Cladding on Substrate of Cast Irons." Materials Science Forum 909 (November 2017): 33–38. http://dx.doi.org/10.4028/www.scientific.net/msf.909.33.

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Due to high content of carbon and poor weldability, the ultrasonic frequency induction cladding technique was utilized to fabricate Ni-based alloy coating on the substrate of gray cast irons. In order to investigate the microstructure and properties of Ni-based alloy coating, the techniques of optical microscopy (OM), backscattered electron image (BEI), X-ray diffraction (XRD) and Vickers microhardness tester were employed. And then the immersion test and potentiodynamic polarization measurement were performed to evaluate the corrosion behavior of Ni-based alloy coating. The experimental results reveal that the coating bonds metallurgically with the substrate. Due to the elemental interdiffusion between the coating and the substrate, a solid solution zone of coating is formed. The phases of γ-Ni, Ni3B, NiSi, chromium borides and carbides can be distinguished in the coating. Chromium borides and carbides are benefit for the improvement of hardness and NiSi provides good corrosion resistance.

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Gong, Jian Hong, Shu Xia Lin, and Jun Gao. "Chemical Composition and Structure of the Boride Inclusions in Synthetic Diamonds Grown under HPHT." Advanced Materials Research 279 (July 2011): 101–5. http://dx.doi.org/10.4028/www.scientific.net/amr.279.101.

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Boride inclusions in the synthetic diamond single crystals grown from Fe-Ni-C-B system under high temperature and high pressure were studied in the present paper. Both chemical composition and structure of the inclusions incorporated into the diamond during the process of diamond growth were successfully determined by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). It was found that the inclusions related to boron trapped in the diamond consisted of f.c.c. (FeNi)23(CB)6, (FeNi)3(CB), Fe2B, FeB, hexagonal Ni3B, and B4C.

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Xu, Junfeng, Di Zhang, Feng Liu, and Zengyun Jian. "Multi-transformations in rapid solidification of highly undercooled hypoeutectic Ni–Ni3B alloy melt." Journal of Materials Research 30, no. 21 (October 9, 2015): 3307–15. http://dx.doi.org/10.1557/jmr.2015.295.

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28

Wang, Xiang, Xiao Dong Sun, Er Yong Liu, Zhi Ming Zhou, Zhi Xiang Zeng, and Xue Dong Wu. "Microstructure and Tribological Properties of Ni-Base Coatings under Different Lubrication Conditions." Materials Science Forum 816 (April 2015): 54–63. http://dx.doi.org/10.4028/www.scientific.net/msf.816.54.

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In order to improve the tribological properties of aluminum alloy cylinder wall, Ni-base coatings were fabricated by atmospheric plasma spraying on aluminum substrate. The composition, microstructure characterization and tribological properties of Ni-base coatings were investigated under different lubrication conditions. The results showed that as-sprayed Ni-based coatings were mainly consisted of γ-Ni solid solution, Ni3B, Cr7C3, Cr6C and Cr3B2 phase. The microstructure of coatings exhibited excellent deposit integrity and density, whilst a typical lamellar structure was observed because the molten droplets successively impinged and spread on the substrate or previously deposited layers to form continuous splats. Friction and wear testing results showed that Ni-based coating performs better than grey cast iron HT200 for the actual application of cylinder block and cylinder liner, especially under boundary lubrication. It was proposed that the excellent mechanical properties ensure the as-sprayed coating with low friction coefficient and wear rate under different lubrication conditions, In addition, the existence of pores was benefitted for the improvement of tribological properties under boundary lubrication.

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29

Li, Guo-lu, Ya-long Li, Tian-shun Dong, Hai-dou Wang, Xiao-dong Zheng, and Xiu-kai Zhou. "Microstructure and Wear Resistance of TIG Remelted NiCrBSi Thick Coatings." Advances in Materials Science and Engineering 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/8979678.

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The self-fluxing NiCrBSi coatings with 800 μm thickness were prepared on the surface of AISI1045 steel substrate by plasma spraying. And the remelted coating was obtained using by the tungsten inert gas (TIG) arc process. The microstructure, surface roughness, hardness, phase composition, and wear resistance of the sprayed coating and remelted coating were systematically investigated. The results demonstrate that TIG remelted treatment can significantly eliminate the microscopic defects in thick coating and improve its density. The surface roughness (Ra) of the remelted coating is only 18.9% of the sprayed coating. The hardness of the remelted coating is 26.8% higher than that of the sprayed coating. The main phases in the sprayed coating are changed from γ-Ni, Cr7C3, and Cr2B to γ-Ni, Cr23C6, CrB, Ni3B, and Fe3C. The wear mass loss of the remelted coating is only 17.1% of the sprayed coating. Therefore, a Ni-based thick coating with good wear resistance can be obtained by plasma spraying and remelted technique.

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30

Liu, Shuang, Shi Hong Shi, Ge Yan Fu, and Hong Pu Wei. "Laser Cladding of Ni-Based Hardfacing Alloy Replacing Stellite06." Key Engineering Materials 464 (January 2011): 647–50. http://dx.doi.org/10.4028/www.scientific.net/kem.464.647.

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For the disadvantages of Co element, such as rarity, high price and nuclear pollution, the Co-based materials will be eliminated in the valves which are used in the third and fourth-generation nuclear plants. In this paper, the composition of a Co-free Ni-based alloy was designed. With laser cladding technology, the Ni-based coatings were obtained. Microstructure of the coatings was characterized by optical microscopy (OM) and scanning electron microscopy (SEM). The phases in the surface layer were identified by X-ray diffraction (XRD) and energy-dispersive spectrometer (EDS). And the wear resistance of the coatings were tested and compared with Co-based alloy. The results showed that the coatings were mainly made of dendrite phases and interdendritic constituents. The dendrites were characterized of primary dendrites M7C3 and M23(CB)6 and some Ni3Al round particles uniformly dispersed in the γ-Ni matrix. There were a bit of Ni3B and Ni3Si phases in the coatings. The wear volume loss of Ni-based alloy was close to of Co-based alloy.

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31

Xia, Dan, Bin Shi Xu, Yao Hui Lv, Yi Jiang, and Cun Long Liu. "Microstructure and Properties of Ni-Base Coatings Obtained by Micro-Plasma Arc Cladding Processes." Advanced Materials Research 154-155 (October 2010): 1371–74. http://dx.doi.org/10.4028/www.scientific.net/amr.154-155.1371.

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Microstructure and properties of Ni-base coatings obtained by micro-plasma arc cladding was investigated. A uniform clad coating was obtained after optimizing the cladding parameters by using NiCrBSi powder. Microstructure of the coatings observed by optical and scanning electron microscopy (SEM) indicated a homogenized microstructure. It has no evident heat-affected zone and no porosity. The phase of the coating was formed by γ-N solid solution, nickel boride Ni3B, carbide Cr21.34Fe1.66C6 and Cr2B3 type chromium boride. Although it likes the laser cladding coatings, micro-plasma coatings has its own characteristic. In addition, the average microhardness and nanohardness of coatings which were much higher than the substrate were observed, and the distribution of the microhardness was drawn.

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Yang, Fang, Zhi Meng Guo, Jun Jie Hao, and Yong Liang Shi. "Self-Propagating High-Temperature Synthesis of TiB₂-Ti(C, N) Cermets Composite Powder." Advanced Materials Research 468-471 (February 2012): 1247–50. http://dx.doi.org/10.4028/www.scientific.net/amr.468-471.1247.

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The ultra-fine TiB2-Ti(C, N) composite powders were prepared by self-propagating high-temperature synthesis (SHS) with Ti, BN and C powders as its starting materials. The morphology of the products was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results showed the composite powders were consisted of the mainly phases Ti(C, N), TiB2 and a small amount of TiN phase. With the Ni addition, the brittle phase Ni3B was appeared. SEM results revealed that the composite powders had a uniform particle size, a round grain-shaped structure and a narrow size distribution and the average particle size of which is less than 1μm.

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Chen, Wenjing, Hui Chen, Yongjing Wang, Congchen Li, and Xiaoli Wang. "Characteristics of Ni–Cr–Fe laser clad layers on EA4T steel." International Journal of Modern Physics B 31, no. 16-19 (July 26, 2017): 1744031. http://dx.doi.org/10.1142/s0217979217440313.

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The Ni–Cr–Fe metal powder was deposited on EA4T steel by laser cladding technology. The microstructure and chemical composition of the cladding layer were analyzed by optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The bonding ability between the cladding layer and the matrix was measured. The results showed that the bonding between the cladding layer and the EA4T steel was metallurgical bonding. The microstructure of cladding layer was composed of planar crystals, columnar crystals and dendrite, which consisted of Cr2Ni3, [Formula: see text] phase, M[Formula: see text]C6 and Ni3B phases. When the powder feeding speed reached 4 g/min, the upper bainite occurred in the heat affected zone (HAZ). Moreover, the tensile strength of the joint increased, while the yield strength and the ductility decreased.

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TIANYUAN, Geng, and Cunshan WANG. "Influence of Graphene Sheet on Microstructure and Properties of Ni-based Alloy Coatings Prepared by Laser Cladding." Materials Science 25, no. 3 (May 10, 2019): 252–58. http://dx.doi.org/10.5755/j01.ms.25.3.19173.

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Ni-based alloy cladding layers with different graphene sheet additions were prepared by laser cladding on the 40CrNi2Si2MoV steel substrate. The influence of the graphene sheet on the microstructure and properties of the cladding layers was investigated. The results show that owing to the diffusion-reaction dissolution, the graphene sheet addition does not bring a corresponding change in the phase constitutions of the cladding layers, i. e., the cladding layers are still composed of γ-Ni, Ni3B, and M7C3 phases. But what has changed is that the solidified structure is refined, and the volume fractions of the eutectic and the carbide are increased with the increase of graphene sheet addition. As a result, the hardness and the wear resistance of the cladding layers gradually increase, whereas the friction coefficient firstly decreases and then increases, with the lowest friction coefficient obtained at 0.5 vol.% graphene sheet addition. Compared to the Ni-based alloy cladding layers with micro-size graphite additions, the studied cladding layers exhibit improved hardness and wear resistance, good forming quality, and increased friction coefficient. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.19173

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35

Ilinykh, Nina, Anastasia Krivorigova, Boris Gelchinski, Sergey Ilinykh, and Leonid Kovalev. "Thermodynamic modeling of composition and propereties of self-fluxing materials based on the nickel." MATEC Web of Conferences 329 (2020): 02026. http://dx.doi.org/10.1051/matecconf/202032902026.

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Self-fluxing nickel or cobalt-based alloys that use boron, phosphorus or silicon, as melting point depressants and fluxing agents are thermodynamic simulation of self-fluxing materials Ni-0.5C-15Cr-3.2Si-2B (PGSR-2) and Ni-1C-17Cr-4.1Si-3.6B (PGSR-4) was performed. As the software for simulation of phase and chemical equilibrium the TERRA software package was used. The simulation was carried out in the temperature range 300–3000 K at a total pressure P = 105 Pa in an argon atmosphere. The temperature dependences of the equilibrium composition and thermodynamic characteristics (enthalpy, entropy, and Gibbs energy) of the alloys of the investigated systems were calculated. It is shown that Ni, Cr, C, Ni3B, Ni2B, NiB, Ni2Si, NiSi, CrB, CrSi can be formed in the condensed phase under equilibrium heating of PGSR-2. When PGSR-4 is heated in the condensed phase, along with the above components, Cr5B3, CrB2 and Cr3C2 compounds can be formed. The temperature dependences of the thermodynamic characteristics of the systems studied have kinks that can be explained by phase transformations.

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36

Shahzad, Khurram, Muhammad Bilal Tahir, and M. Sagir. "Engineering the performance of heterogeneous WO3/fullerene@Ni3B/Ni(OH)2 Photocatalysts for Hydrogen Generation." International Journal of Hydrogen Energy 44, no. 39 (August 2019): 21738–45. http://dx.doi.org/10.1016/j.ijhydene.2019.06.148.

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Yang, Fulin, Pengyu Han, Na Yao, Gongzhen Cheng, Shengli Chen, and Wei Luo. "Inter-regulated d-band centers of the Ni3B/Ni heterostructure for boosting hydrogen electrooxidation in alkaline media." Chemical Science 11, no. 44 (2020): 12118–23. http://dx.doi.org/10.1039/d0sc03917a.

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Zhai, Lu Lu, Jun Wei Zhang, and Chun Yan Ban. "Influence on the Microstructure of Laser Cladding NiCrBSi Coatings with Electromagnetic Compound Field." Solid State Phenomena 295 (August 2019): 15–20. http://dx.doi.org/10.4028/www.scientific.net/ssp.295.15.

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A NiCrBSi coating was produced on a pure iron plate by laser cladding technology. Electric-magnetic compound field was applied in order to improve the quality of coating. The effect of electric-magnetic compound field on the microstructure and the phase composition of coating was investigated by OM and XRD, respectively. The results indicated that the phase composition of the coatings were γ-(Fe,Ni), Cr23C6, Cr7C3, CrB and Ni3B with and without electromagnetic field. Microstructural observation showed that the grains were refined obviously by electromagnetic stirring. The electromagnetic stirring could change the direction of the heat dissipation and changed the direction of the columnar crystal at the bottom of the coating. High qualitative coating without porosity were obtained under electromagnetic field.

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Li, Ouyang, Guirong Yang, Wenming Song, Dawen Gao, and Xianming Sun. "Microstructure and polarization behavior of Ni/WC+GO (graphene oxide) composite cladding fusion coating." International Journal of Materials Research 112, no. 4 (March 19, 2021): 308–20. http://dx.doi.org/10.1515/ijmr-2020-7765.

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Abstract Ni/WC/graphene oxide (GO) composite cladding fusion coatings were fabricated through the vacuum cladding technique on a medium carbon structure steel (45# steel) substrate whose carbon content was 0.45 ± 0.03%. The microstructural characteristics, phase composition, and electrochemical polarization characteristics of the composite cladding fusion coatings were analyzed with scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and the electrochemical workstation CHI660E. Results show that the microstructure was compact and was micro-crack free, and without inclusions or other defects. It was comprised of four micro-zones, namely, the composite, transition, diffusion fusion, and diffusion-affected zones with thicknesses of approximately 4 mm, 1 mm, 20 μm, and 250 μm, respectively. The main phases of the composite coating were γ-Ni solid solution, WC, Cr7C3, Ni2.9Cr0.7Fe0.36, Cr23C6, Ni3Fe, Ni3Si, Ni3B, W2C, and C. The self-corrosion potential of the composite coatings had increased by 0.3269 V compared with that of the substrate, and the corrosion current density of the composite coatings had decreased by nearly two orders of magnitude. The Ni-based solid solution region with relatively high C and Cr contents was difficult to dissolve.

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40

Guo, Yong Qiang, Hong Wei Zhao, and Rong Lu Sun. "Microstructure and Wear Properties of Laser-Clad NiCrBSi Coating." Advanced Materials Research 291-294 (July 2011): 105–8. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.105.

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NiCrBSi coating was prepared on the surface of 45 steel by CO2 laser. The microstructure of the clad layer was characterized by SEM、EDS and XRD. The microhardness and wear resistance of the laser clad layer was examined. The results show that laser clad layer can be achieved under technical processing parameters and that the good metallurgical bonding is formed between the coating and substrate. The coating is uniform, continuous and free of pores and cracks. The microstructure of the coating is mainly composed of g-Ni, Ni3B, CrB and Cr23C6 particles. The microhardness of the coating (500～650HV0.2) is distinctly higher than that of the substrate(240～250 HV0.2). The clad layer is reinforced by particles and grain-refining, resulting in greatly increase in wear resistance comparing with 45 steel.

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41

Xu, Jin Fu, Xiao Qin Ding, Xiao Yun Han, Hang You, Xian Rui Wang, and Cui Liang. "Microstructure and Properties of Ni60 Self-Fluxing Alloy Coatings Fabricated by Spark Plasma Sintering." Applied Mechanics and Materials 52-54 (March 2011): 639–46. http://dx.doi.org/10.4028/www.scientific.net/amm.52-54.639.

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We report the fabrication of Ni60 self-fluxing alloy coatings on the substrate of 45 steel via spark plasma sintering technique. The microstructure and interface bonding of the coatings have been investigated systematically. The results suggest that the as-prepared coatings possess fine grains, little porosity and with hard-phases (CrB, Cr7C3, Ni3B) dispersed within the substrate (γ-Ni). The coatings are jagged and embedded to the substrate due to the elements diffusion during the SPS process. A solid interfacial metallurgy bonding can be achieved between the coating and substrate and the hardness of the coating is ~597.5 HV0.3. The hardness of the transition layer present a gradient distribution ranged from 597.5 HV0.3 to 209.6 HV0.3. The bonding strength between the coating and substrate is measured to be ~710MPa. The volume abrasive wear rate of the coating is ~5.43 × 10-2cm3.

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42

Desseaux-Thibault, J., and S. Hamar-Thibault. "Analysis by scanning electron microscopy and structure determination by high resolution electron microscopy of ni/ni3b eutectic." Surface and Interface Analysis 9, no. 3 (July 1986): 175–80. http://dx.doi.org/10.1002/sia.740090308.

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43

Wang, Rui, Changyao Ouyang, Qihang Li, Qiaofeng Bai, Chunjiang Zhao, and Yingliang Liu. "Study of the Microstructure and Corrosion Properties of a Ni-Based Alloy Coating Deposited onto the Surface of Ductile Cast Iron Using High-Speed Laser Cladding." Materials 15, no. 5 (February 22, 2022): 1643. http://dx.doi.org/10.3390/ma15051643.

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To improve the surface corrosion resistance of ductile iron, Ni-based alloy coatings were prepared using a high-speed laser cladding technology with different levels of laser power. The microstructure, phases, and corrosion properties of the coatings were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and an electrochemical workstation. Variations in laser power did not change the main phases of the coatings, which were composed of γ-Ni, Ni3B, Ni2Si, and Cr23C6. With an increase in power, the degree of segregation in the coating decreased, sufficient melting between elements was achieved, and the chemical composition became more uniform. Enhancement of the laser power resulted in more energy being injected into the cladding, which allowed adequate growth of tissue, and dendrites continued to grow in size as the power increased. The self-corrosion potentials of the coatings at laser power levels of 1.6, 2.0, and 2.4 kW were −625.7, −526.5, and −335.7 mV, respectively. The corrosion potential of the 2.4 kW coating was the highest, and the corroded surface of the cladding layer included mainly sizeable continuous structures with a light degree of corrosion and the highest corrosion resistance.

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44

Zhao, Longjie, Huijun Yu, Yanxiang Wang, Zhihuan Zhao, Weihai Song, and Chuanzhong Chen. "NiCrBSi Coatings Fabricated on 45 Steel Using Large Spot Laser Cladding." Materials 15, no. 18 (September 8, 2022): 6246. http://dx.doi.org/10.3390/ma15186246.

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Ni35 coatings were fabricated on 45 steel using a CO2 laser at various parameters. A relatively large spot (10 mm diameter) was adopted, which was beneficial to the coating quality and the cladding efficiency. The cross-sectional geometry, phase constituent, and microstructure of the coatings were investigated. With a lower specific energy, coating height increased, while coating width, melted depth, dilution rate, width to height ratio and contact angle decreased. Ni35 coating primarily consisted of γ-Ni, FeNi3, Ni3B, Cr23C6, and Cr5B3. Dendrites with flower-like, fishbone-like, pearl-like, and column-like morphologies were observed. The fraction of flower-like dendrites increased gradually with the decrease in scanning velocity due to the dendrite growth direction evolution. With the decrease in scanning velocity, the microstructure of the heat-affected zone transformed from martensite to martensite + sorbite and finally sorbite. The maximum microhardness of the Ni35 coating reached 451.8 HV0.2, which was about double that of the substrate (220 HV0.2).

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Qian, Shaoxiang, Yibo Dai, Yuhang Guo, and Yongkang Zhang. "Microstructure and Wear Resistance of Multi-Layer Ni-Based Alloy Cladding Coating on 316L SS under Different Laser Power." Materials 14, no. 4 (February 7, 2021): 781. http://dx.doi.org/10.3390/ma14040781.

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We prepared three kinds of Ni based alloy cladding coatings on 316L stainless steel at different power levels. The microstructure of the cladding layer was observed and analyzed by XRD, metallographic microscope, and SEM. The hardness of the cladding layer was measured, and the wear resistance of it was tested by a friction instrument. The results show that the effect of laser cladding is good, and it has good metallurgical bonding with the substrate. Different microstructures such as dendritic and equiaxed grains can be observed in the cladding layer. With the increase in laser power, more equiaxed and columnar dendrites can be observed. The phase composition of the cladding layer is mainly composed of γ–Ni solid solution and some intermetallic compounds such as Ni3B, Cr5B3, and Ni17Si3. The results of EDS show that there are some differences in the distribution of C and Si between dendrites. The hardness of the cladding layer is about 600 HV0.2, which is about three times of the substrate (~200 HV0.2). Through the analysis of the wear morphology, the substrate wear is serious, there are serious shedding, mainly adhesive wear, and abrasive wear. However, the wear of the cladding layer is slight, which is abrasive wear, and there are some grooves on the surface.

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Vernekar, Amit Ashok, Sandesh Tukaram Bugde, and Santosh Tilve. "Sustainable hydrogen production by catalytic hydrolysis of alkaline sodium borohydride solution using recyclable Co–Co2B and Ni–Ni3B nanocomposites." International Journal of Hydrogen Energy 37, no. 1 (January 2012): 327–34. http://dx.doi.org/10.1016/j.ijhydene.2011.09.033.

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47

Kamdi, Zakiah, and K. T. Voisey. "Corrosion Mechanism of Tungsten Carbide-Based Coatings in Different Aqueous Media." Key Engineering Materials 694 (May 2016): 167–71. http://dx.doi.org/10.4028/www.scientific.net/kem.694.167.

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In cermet coatings with both ceramic and metal present, these can have very different corrosion potentials. Therefore, determination of the corrosion behaviour performance and its mechanism is crucial, especially in very acidic and alkaline environment. A conventional high velocity oxy-fuel (HVOF) tungsten carbide (WC)-Co coatings and a weld overlay tungsten carbide-nickel alloy cermet with carbide size of ~0.3-5 mm and ~50-140 mm respectively are used. Potentiodynamic tests are carried out in acidic and alkaline electrolytes: 0.5 M sulphuric acid, pH 0.45 and bentonite drilling fluid, pH 10.45. The behaviour of both coating types tested were pH dependent. The HVOF coating showed preferential dissolution of the binder in both electrolytes, with material loss being approximately twice as severe in the 0.5 M sulphuric acid compared to the alkaline drilling fluid. For the weld overlay coatings, with the larger carbide particles, the Ni3B phase in the binder was preferentially removed in the acidic electrolyte whereas the Ni rich dendritic phase underwent preferential dissolution in the alkaline environment.

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48

Bergant, Zoran, Barbara Šetina Batič, Imre Felde, Roman Šturm, and Marko Sedlaček. "Tribological Properties of Solid Solution Strengthened Laser Cladded NiCrBSi/WC-12Co Metal Matrix Composite Coatings." Materials 15, no. 1 (January 4, 2022): 342. http://dx.doi.org/10.3390/ma15010342.

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NiCrBSi, WC-12Co and NiCrBSi with 30, 40 and 50 wt.% WC-12Co coatings were produced on low carbon steel by laser cladding with an Nd:YAG laser with a multi-jet coaxial cladding-nozzle. The microstructure properties after WC-12Co alloying were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and Vickers hardness tests. The resulting microstructures consisted of a γ-Ni and Ni3B matrix, strengthened with Co and W, Ni3Si, CrB, Cr7C3, Cr23C6, WC/W2C phases. In coatings with 30, 40 and 50 wt.% WC-12Co, a solid solution, strengthened multi-matrix NiCrWCo phase formed, which yielded a higher matrix hardness. Wear tests that monitored the friction coefficients were performed with a tribometer that contained a ball-on-disc configuration, Al2O3 counter-body and reciprocal sliding mode at room temperature. The major wear mode on the NiCrBSi coatings without the WC-12Co was adhesive with a high wear rate and visible material loss by flaking, delamination and micro-ploughing. The addition of WC-12Co to the NiCrBSi coating significantly increased the wear resistance and changed the major wear mechanism from adhesion to three-body abrasion and fatigue wear.

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Lu, Xinyong, Jun Xie, Shu-yuan Liu, Andrzej Adamski, Xiaobo Chen, and Xin Li. "Low-Cost Ni3B/Ni(OH)2 as an Ecofriendly Hybrid Cocatalyst for Remarkably Boosting Photocatalytic H2 Production over g-C3N4 Nanosheets." ACS Sustainable Chemistry & Engineering 6, no. 10 (August 30, 2018): 13140–50. http://dx.doi.org/10.1021/acssuschemeng.8b02653.

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Qian, Shaoxiang, Yongkang Zhang, Yibo Dai, and Yuhang Guo. "Microstructure and Mechanical Properties of Nickel-Based Coatings Fabricated through Laser Additive Manufacturing." Metals 11, no. 1 (December 29, 2020): 53. http://dx.doi.org/10.3390/met11010053.

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In this study, single-layer and three-layer nickel-based coatings were fabricated on 316L SS by laser additive manufacturing. The phase characterization, microstructure observation, and microhardness analysis of the coatings were carried out by X-ray diffraction (XRD), scanning electron microscope (SEM), and microhardness tester. And the wear resistance of the coatings was analyzed through dry sliding friction and wear test. The results show that the cross-section microstructure of the three-layer nickel-based coating is different from that of the single-layer one under the influence of heat accumulation; the dendrite structure in the central region of the former is equiaxial dendrite, while that of the latter still remains large columnar dendrites. The existence of solid solution phase γ-(Fe, Ni) and hard phases of Ni17Si3, Cr5B3, Ni3B in the coating significantly improve the wear resistance of the coating, and the microhardness is nearly 2.5 times higher than that of the substrate. However, the average microhardness of multilayer cladding coating is about 48 HV0.2 higher than that of the single-layer cladding coating. In addition, the fine surface structure of the three-layer nickel-based coating improves the wear resistance of the coating, making this coating with the best wear resistance.

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Journal articles on the topic 'Ni-Ni3B'

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