Fabrication and Performance of Ni-Co-P/Si3N4 Electroplated Composite Coatings on Al-Si Alloys

2013 ◽  
Vol 377 ◽  
pp. 235-239
Author(s):  
Yun Li ◽  
Liang Fang ◽  
Wei Dong Shen ◽  
Sheng Chun Wang ◽  
Chun Lan Cao ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Electric Current ◽  
Current Density ◽  
Composite Coatings ◽  
Adhesive Force ◽  
Optical Microscope ◽  
Electric Current Density ◽  
Electro Deposition ◽  
X Ray ◽  
Hardness Tester

In order to improve the wear resistance of Al-Si alloys, the electro deposition of Ni-Co-P/Si3N4coating on a hypereutectic Al-Si casting alloy was studied in this paper. The thickness, hardness, surface morphology, composition, adhesive force and wear resistance of Ni-Co-P/Si3N4coating were measured by optical microscope, micro-hardness tester, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), adhesive attraction scratcher and abrasion tester. It was shown that Si3N4particulates were uniformly distributed in the composite coating. And the effect of process parameters, such as electric current density, temperature, PH, plating time and component of electroplating bath,were obtained. The wear resistance of the coating was improved with the increase of hardness and the content of Si3N4in the coating. It was also improved by decreasing electric current density. The adhesion of the coating was poor for increasing the content of P and Co in the coating. At the same time, the coating was hard, friable, and easy to be broken with the decrease of temperature.

scholarly journals Effect of Current Density on the Performance of Ni–P–ZrO2–CeO2 Composite Coatings Prepared by Jet-Electrodeposition

Coatings ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 616
Author(s):  
Zhaoyang Song ◽  
Hongwen Zhang ◽  
Xiuqing Fu ◽  
Jinran Lin ◽  
Moqi Shen ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Current Density ◽  
Composite Coatings ◽  
Electrochemical Corrosion ◽  
Corrosion Current ◽  
X Ray Diffraction ◽  
X Ray ◽  
Jet Electrodeposition ◽  
Electrochemical Corrosion Resistance

The objective of this study was to improve the surface properties, hardness, wear resistance and electrochemical corrosion resistance of #45 steel. To this end, Ni–P–ZrO2–CeO2 composite coatings were prepared on the surface of #45 steel using the jet-electrodeposition technique by varying the current density from 20 to 60 A/dm2. The effect of current density on the performance of the composite coatings was evaluated. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) were applied to explore the surface topography, elemental composition, hardness and electrochemical corrosion resistance of the composite coatings. The results showed that with the increase in the current density, the hardness, wear resistance, and electrochemical corrosion resistance tends to increase first and then decrease. At a current density of 40 A/dm2, the hardness reached a maximum of 688.9 HV0.1, the corrosion current reached a minimum of 8.2501 × 10−5 A·cm−2, and the corrosion potential reached a maximum of −0.45957 V. At these values, the performance of the composite coatings was optimal.

Microstructure and Tribological Properties of Ni-Co/SiC Coatings Prepared by Occlusion Electroplating for Grinding Tools

2010 ◽  
Vol 34-35 ◽  
pp. 1457-1461
Author(s):  
Ye Fa Tan ◽  
Bin Cai ◽  
Yi Qiang Tu ◽  
Ting Xu ◽  
Hua Tan ◽  
...  
Keyword(s):  
Electric Current ◽  
Tribological Properties ◽  
Current Density ◽  
Composite Coatings ◽  
Great Influence ◽  
Matrix Alloy ◽  
Electric Current Density ◽  
Electroplating Process ◽  
Sic Coatings ◽  
Abrasive Size

In order to improve the grinding performance and service life of electroplating composite coatings with high percent of hard abrasives, the composite coatings of Ni-Co/SiC were prepared by occlusion electroplating technology and their microstructure and tribological properties were studied. The research results show that the cathodal electric-current density in occlusion electroplating process and the SiC abrasive size have great influence on microstructure and tribological properties of Ni-Co/SiC coatings. The optimum value of cathodal electric-current density is 1 A/dm2 and the proper SiC abrasive size is about 20 μm, in which the Ni-Co/SiC coatings have excellent wear resistance and high grinding ability. The main wear mechanisms of Ni-Co/SiC coatings are micro-cutting and adhesive wear of matrix alloy, and micro-cracking wear and spalling of SiC abrasives.

scholarly journals The effect of simplifications of a numerical mesh on the results of electromagnetic analysis of the Nuclotron-type cable

2018 ◽  
Vol 177 ◽  
pp. 08004
Author(s):  
Łukasz Tomków
Keyword(s):  
Magnetic Field ◽  
Electric Current ◽  
Current Density ◽  
Electric Current Density ◽  
Electromagnetic Analysis ◽  
First Case ◽  
Single Region ◽  
The Magnetic Field

The model of a single Nuclotron-type cable is presented. The goal of this model is to assess the behaviour of the cable under different loads. Two meshes with different simplifications are applied. In the first case, the superconductor in the cable is modelled as single region. Second mesh considers individual strands of the cable. The significant differences between the distributions of the electric current density obtained with both models are observed. The magnetic field remains roughly similar.

Visualization of Water Distribution in Operating PEMFC Using X-Ray Microscopy

2009 ◽  
Author(s):  
Jongrok Kim ◽  
Junho Je ◽  
Massoud Kaviany ◽  
Sang Young Son ◽  
MooHwan Kim
Keyword(s):  
Electric Current ◽  
Spatial Resolution ◽  
Current Density ◽  
Water Distribution ◽  
Active Area ◽  
X Ray ◽  
Electric Loader ◽  
Pohang Accelerator Laboratory

In this investigation, X-ray microscopy (7B2) in Pohang Accelerator Laboratory was employed to visualize the water distribution in operating PEMFC which had 2cm × 2cm active area. This X-ray microscopy has 1μm spatial resolution with 1.5mm × 1.2mm view area. Each image spent about 1.3 second, 0.65 second for exposure and about 0.6 second for data read out. The resistance of the electric loader was changed and electric current and voltage was measured during images were recorded. The water distribution in PEMFC was analyzed with this I-V curve. Water distribution was depend on current density and aggregated on interfaces of layers (GDL, MPL, MEA).

MICROSTRUCTURE AND WEAR RESISTANCE OF IN-SITU SYNTHESIZED TiB2–TiC/Fe COMPOSITE COATING BY LASER CLADDING

2020 ◽  
pp. 2050046
Author(s):  
TIANWEI YANG ◽  
ZHAOHUI WANG ◽  
SHIHAI TAN ◽  
FU GUO
Keyword(s):  
Wear Resistance ◽  
Laser Cladding ◽  
Composite Coatings ◽  
X Ray Diffraction ◽  
Mixed Powder ◽  
X Ray ◽  
Material Surfaces ◽  
Metallurgical Bonding ◽  
Steel Surfaces

To increase the strength and wear resistance of material surfaces, various combinations of B4C and 80TiFe powder were mixed into a Fe60 self-fluxing alloy powder; the composite coatings reinforced by TiB2–TiC were successfully prepared on Q235 steel surfaces by laser cladding. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) were used to study the microstructure and chemical and phase composition. Microhardness and wear testers were used to investigate the mechanical properties. The results show that the interfaces of composite coatings and substrate materials are excellent for metallurgical bonding. The block-like TiB2 particles and flower-like TiC particles are uniformly distributed in the cladding coating. When the mass fraction of the mixed powder is 30%, the average microhardness of the coating is approximately 1100 HV[Formula: see text], which is 50% higher than that without the mixed powder, and demonstrates the best wear with a performance twice as better as that of the substrate.

MICROSTRUCTURE AND DRY SLIDING WEAR RESISTANCE OF LASER CLADDING Ti-Al-Si COMPOSITE COATING

2017 ◽  
Vol 24 (Supp01) ◽  
pp. 1850009 ◽  
Author(s):  
H. X. ZHANG ◽  
H. J. YU ◽  
C. Z. CHEN ◽  
J. J. DAI
Keyword(s):  
Wear Resistance ◽  
Laser Cladding ◽  
Composite Coatings ◽  
Energy Dispersive Spectrometer ◽  
Wear Test ◽  
Dry Sliding Wear ◽  
Test Machine ◽  
Transmission Microscopy ◽  
Hardness Tester ◽  
Three Samples

In order to improve the wear resistance of Ti alloys, different mass ratios of Ti-Si-Al powders were designed to fabricate hard phases reinforced intermetallic matrix composite coatings on the Ti-6Al-4V substrate by laser cladding. The corresponding coatings were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and high resolution transmission microscopy (HRTEM). The HV-1000 hardness tester and MM200 wear test machine were employed to test the hardness and the wear resistance of the composite coatings, respectively. The composite coatings mainly consisted of the reinforcements of Ti5Si3, Ti3AlC2 and Ti7Al5Si[Formula: see text] and the matrix of Ti3Al, TiAl, TiAl3 and [Formula: see text]-Ti. The micro-hardness of the Ti-35Al-15Si coating was from 956 HV[Formula: see text] to 1130 HV[Formula: see text], which was approximately 3–4 times of the substrate and the highest in the three samples. The wear rate of the Ti-35Al-15Si coating was 0.023[Formula: see text]cm3[Formula: see text][Formula: see text][Formula: see text]min[Formula: see text], which was about 1/4 of the Ti-6Al-4V substrate. It was the lowest in the three samples.

Study on Aging Strengthening of Mg-Zn-Cu Alloy Based on Component Optimization Design

2016 ◽  
Vol 873 ◽  
pp. 33-37
Author(s):  
Jie Ye ◽  
Xiao Ping Lin ◽  
Yun Dong ◽  
Bo Li ◽  
Gao Peng Xu ◽  
...  
Keyword(s):  
Optimization Design ◽  
Optical Microscope ◽  
X Ray Diffraction ◽  
Strengthening Phase ◽  
X Ray ◽  
Hardness Tester ◽  
Cu Alloy ◽  
Factsage Software ◽  
Kinetics Of ◽  
Zn Alloy

In this study, we investigated the aging strengthening of Mg-Zn-Cu alloy based on component optimization design by FactSage software, optical microscope (OM), X-ray diffraction (XRD) and Vickers hardness tester. The results show that the precipitation rate of MgZn2 phase in Mg-6Zn-1Cu is significantly higher than that of the other alloys. When Mg-6Zn-1Cu alloy is subjected to aging at 160<strong>°C</strong> for different time, the phase consists of α-Mg, MgCu2 and MgZn2. The content of main strengthening phase MgZn2 is increasing with the prolonging of aging time. When Mg-6Zn-1Cu alloy aged at 160<strong>°</strong><strong>C</strong> for 10h, the kinetics of precipitation is considerably accelerated. The results indicate that the hardening produced in the Cu-containing alloy is considerably higher than in the Mg-Zn alloy. Therefore, based on component optimization design to establish Mg-Zn-Cu alloy solidification database, and to predict the phase equilibrium and thermodynamic properties of the alloy, is an effective method for the development of new magnesium alloy.

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