Nickel-coated Carbon Fibers Research Articles

RETRACTED: Fabrication and electromagnetic characteristics of microwave absorbers containing Li0.35Zn0.3Fe2.35O4 micro-belts and nickel-coated carbon fibers

This article has been retracted: please see Elsevier Policy on Article Withdrawal ( http://www.elsevier.com/locate/withdrawalpolicy ). This article has been retracted at the request of the Editor-in -Chief. The authors have plagiarized part of a paper that had already appeared in Ceram. Int., 39 (2013) 2317–2322, http://dx.doi.org/10.1016/j.ceramint.2012.08.079 . One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.

Hydrogen evolution reaction at Pd-modified carbon fibre and nickel-coated carbon fibre materials

The present paper reports on A.C. impedance study of hydrogen evolution reaction (HER), carried-out on Pd-modified carbon fibre (CF) and nickel-coated carbon fibre (NiCCF) materials. The HER was examined in 0.5 M H2SO4 solution for electrochemically deposited Pd on Hexcel 12K AS4C CF and Toho-Tenax 12K50 NiCCF tow materials. Kinetics of the hydrogen evolution reaction was studied at room temperature, over the cathodic overpotential range: −100 to −1200 mV vs. RHE. Corresponding values of charge-transfer resistance, exchange current–density for the HER and other electrochemical parameters for the examined catalyst materials were derived. Thus, Pd modification of CF and NiCCF materials (at ca. 1.5 wt.% Pd) dramatically increased the exchange current–density parameter by about 5300× and 445× for carbon fibre and nickel-coated carbon fibre tows, correspondingly.

Tribological characteristics of innovative Al6061–carbon fiber rod metal matrix composites

Rods made of continuous carbon fibers are being extensively used as structural materials in light weight micro-air vehicles owing to their excellent specific modulus and strength. Further, they possess excellent tribological characteristics – low friction and wear coupled with high conductivity making them an ideal reinforcement in developing light weight, high strength aluminum based metal matrix composites. In the last three decades, researchers have focused mainly on the study of mechanical and tribological behavior of discontinuous carbon fiber reinforced metal matrix composites. However, no information is available regarding the tribological behavior of carbon fibers rod reinforced metal matrix composites, although it is interesting and will result in expanding the applications of metal matrix composites (MMC) where tribological failures are expected.In the light of the above, the present work focuses on development of innovative Al6061–carbon fiber rods composites by casting route and assessing their tribological characteristics. Carbon fiber rods of 4mm and 6mm diameters were surface sensitized to achieve electro less nickel coating. Copper plating on the electro less nickel coated carbon fiber rods were carried out. The copper plated carbon fiber rods were arranged in cylindrical array in the metallic mold to which molten Al6061 alloy after degassing was poured at a temperature of 700°C. The developed innovative composites were subjected to density tests, microstructure studies, hardness, friction and wear tests. A pin on disk configuration was used with hardened steel as the counter face. Load was varied from 20N to 60N while the sliding velocity was varied between 0.12m/s and 0.62m/s. Scanning electron microscopy (SEM) studies on worn surfaces and wear debris have been carried out to validate the wear mechanism. The developed innovative composites (11Vol.% & 25Vol.%) have exhibited lower coefficient of friction and wear rates when compared with matrix alloy.

RETRACTED: Synthesis and microwave absorbing mechanism of two-layer microwave absorbers containing Li0.35Zn0.3Fe2.35O4 micro-belts and nickel-coated carbon fibers

RETRACTED: Synthesis and microwave absorbing mechanism of two-layer microwave absorbers containing Li0.35Zn0.3Fe2.35O4 micro-belts and nickel-coated carbon fibers

J045023 巨大比表面積炭素繊維を用いた異種材料接合([J045-02]知的材料・構造システム(2))

A new method with extremely large friction force by broad interface of carbon fiber (CF : 6μm diameter) coated by nickel (Ni) to prevent TiC formation and to enhance the ability of fiber rapping by molten Ti have been suggested for a joint (Ti/NiCF/CFRP) of carbon fiber reinforced epoxy polymer (CFRP) and titanium (Ti). The new joint part was strengthened by impregnated nickel-coated carbon fiber (NiCF) exhibited the high Charpy impact value (a_<uc>). Results showed overall, the Ti/NiCF/CFRP had higher a_<uc> than the Ti/Glue/Epoxy and Ti/Epoxy at each fracture probability (Pf). Based on the SEM and XRD pattern results, the chemical compound of TiC has not been observed in the Ti/NiCF/CFRP sample. Therefore, we concludes that the Ni coating prevents the formation of TiC in the of the Ti/NiCF/CFRP joint sample. Since molten titanium does not bite the carbon fiber, the Ni coated carbon fiber exhibits to maintain the high strength.

Fabrication of Continuous Nickel-Coated Carbon Fiber Reinforced Aluminum Matrix Composites Using Low Gas Pressure Infiltration Method

Based on the principle of vacuum counter-pressure casting, a low gas pressure infiltration technology was developed to fabricate the Ni-coated carbon fiber reinforced A357 alloy composites. The soundness and microstructure of the as-cast composites were investigated. The results show the relative density increases with the increase of melt temperature, while it firstly increases and then declines as the fiber temperature and infiltration pressure increased. The enhancement of melt and fiber temperature can eliminate the incomplete infiltration defects and improve the uniformity of fiber distribution. The insufficient infiltration pressure leads to some micro-pores in the matrix alloy. However, the over high fiber temperature and infiltration pressure may result in the separation of nickel coating and the fiber aggregation respectively, both of which are responsible for the partial un-infiltrated or insufficient filling defects. The appropriate infiltration parameters identified in this study could provide a reference for inhibition of the hazard interfacial reactions by optimizing the low gas pressure infiltration process.

A new composite material – low-carbon Stellite alloy reinforced with nickel-coated carbon fibers

A group of nickel-coated carbon fiber reinforced Stellite 25 composites are produced using the hot isostatic pressing technique. The focus of this research is on obviating the problems related to the presence of carbides in Stellite alloys by substituting carbides as the main strengthening agent in Stellite alloys with nickel-coated carbon fibers. The principal reason for selecting Stellite 25 is because of its low carbon content and thereby relatively carbide free microstructure. The nickel coating is intended to eliminate any chance of carbide formation due to the possible reaction between carbon fibers and the matrix alloying additions. The tribomechanical and corrosion properties of the composites are characterized. The results show that the composites exhibit better corrosion resistance than medium-carbon Stellite alloys. The addition of carbon fibers into Stellite 25 improves its hardness and tribological properties. The wear rates of the composites are lower than that of medium-carbon Stellite alloys and comparable with that of high-carbon Stellites.

Fabrication and microwave absorbing properties of Li0.35Zn0.3Fe2.35O4 micro-belts/nickel-coated carbon fibers composites

The Li0.35Zn0.3Fe2.35O4 micro-belts were prepared by cotton template for the first time. The nickel-coated carbon fibers were obtained by the electroless plating method. The formation mechanism of the ferrite micro-belt was studied. The microwave absorption properties of the two layers absorbers containing Li0.35Zn0.3Fe2.35O4 micro-belts and nickel-coated carbon fibers composites were investigated in the frequency range of 30–6000MHz. The absorbers of the Li0.35Zn0.3Fe2.35O4 micro-belts/nickel-coated carbon fibers composites have much better microwave absorption properties than the nickel-coated carbon fibers absorbers, and the microwave absorption properties of the composites are influenced by the content of the absorber.

Effect of adding fiber on the microstructure and mechanical properties of NiFe2O4 composite ceramics

NiFe2O4 composite ceramics reinforced with carbon fibers (Cf), nickel-coated carbon fibers (NiCf) and ZrO2 fibers (ZrO2f) were fabricated by the conventional high-temperature solid state reaction at 1300°C for 6hs. The effects of the three kinds of fibers on microstructure and mechanical properties of NiFe2O4 composite ceramics were investigated. The fracture surfaces of NiFe2O4 composite ceramics were observed by scanning electron microscopy (SEM). Elemental analysis of micro-structural phases was performed using energy dispersive spectroscopy (EDS), attached with SEM. Flexural strength by three-point bending techniques and fracture toughness were measured. It was found that leaving holes after reactions between the carbon fiber and matrix led to decreased mechanical properties. The ZrO2f-doped composite had an improved fracture toughness of 3.05±0.1MPam1/2 compared to NiFe2O4 composite ceramics having 1.91±0.2MPam1/2 due to fiber debonding, fiber pull-out and fiber bridging as well as microcracking toughening. The results presented here show that ZrO2f can serve as a potential toughening agent for NiFe2O4 composite ceramics.

Preparation and characterization of nickel-coated carbon nanofibers produced from the electropsinning of polyamideimide precursor

Nickel-coated carbon nanofibers were prepared using an electroless plating method. The carbon fibers were fabricated with polyamideimide (PAI) by electrospinning, and the characteristics of the nickel-coated carbon fibers were then examined to determine the effect of the nickel coating. The carbon fiber structural properties morphology were confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron spectroscopy (SEM). The electrical conductivity of the fibers was measured using a 4-point testing method. The results showed that the electrical conductivity of the fibers increased with as plating time increased. The electrical conductivity increased remarkably in the presence of metallic nickel particles on the carbon fiber surfaces. This experiment established the optimum conditions for plating on the carbon fiber surfaces that provided the best electrical conductivity.

Characterization of an injection-moulded car audio chassis made of polycarbonate–(acrylonitrile–butadiene–styrene)-based composite using metal-coated carbon fibre

Engineering plastics are widely used as a substitute for stainless steel in the automobile industry to reduce weight and to improve fuel efficiency. In this paper, a polycarbonate–(acrylonitrile–butadiene–styrene)-based composite with nickel-coated carbon fibre was developed, and the application of the composite to a lightweight car audio chassis was examined. The mechanical and electrical properties of the composite were evaluated through various physical tests, i.e. tensile, impact, flexural and electromagnetic interference shielding effectiveness tests. In addition, the characteristics of this material were compared with those of a material previously developed by the present authors, i.e. a polycarbonate–(acrylonitrile–butadiene–styrene)-based composite with metal fibre and glass fibre. Finally, the actual car audio chassis was made by injection moulding under various moulding conditions pertaining to the injection speed and the tool temperature to find the optimum injection-moulding conditions. Two required key tests, i.e. a full-scale electromagnetic interference shielding effectiveness test and vibration analysis, were conducted to confirm the applicability of the polycarbonate–(acrylonitrile–butadiene–styrene)-based composite with nickel-coated carbon fibre as a material for a car audio chassis.

Electrodeposition of Nickel onto 12K Carbon Fibre Tow in a Continuous Manner

Nickel-coated carbon fibre (NiCCF) is an important composite material, which finds numerous engineering applications, primarily within: computer, telecommunication, automotive and military industries. In general, NiCCF can be produced by one of the three methods, namely: chemical vapour deposition (CVD), electroless, and electrochemical (galvanic) deposition of Ni on a carbon fibre tow material. The present paper reports a study of the process of nickel electrodeposition (at ultrathin layers of ≈ 0.3–0.5 μm) onto the surface of 12K (12 000 single filaments) carbon fibre (CF) tow, carried-out in a continuous way. In addition, the effect of selected pre-treatments applied to carbon fibre, as well as that of operational parameters of the process, on the quality of the NiCCF product were investigated. (doi: 10.5562/cca1743)

Effect of interface properties on the mechanical performance of carbon fiber/Mg composites fabricated by powder metallurgy

Carbon fiber/magnesium composites were fabricated by powder metallurgy techniques using short carbon fibers electrolessly coated and uncoated by nickel as reinforcement and pure magnesium powder as matrix.SEM-EDS,TEM,XRD and tensile tests were used to characterize their interfacial morphology,elemental composition,phase composition and mechanical properties.Results showed that the carbon fibers were uniformly distributed in the composites and were preferentially oriented parallel to the extrusion direction.The interfacial bonding between carbon fibers and magnesium was improved by the nickel coating.The improvement was achieved by a reaction between the nickel coating on the fibers and magnesium to form Mg2Ni.The reinforcing effect of the nickel-coated carbon fibers was achieved by interfacial load transfer as evaluated by comparing the measured yield strengths with the theoretical values.

Magnetic alignment of nickel-coated carbon fibers

Magnetic composites of nickel-coated carbon nanofibers have been successfully fabricated by employing a simple microwave-assisted procedure. The scanning electron microscopy images show that a complete and uniform nickel coating with mean size of 25 nm could be deposited on carbon fibers. Magnetization curves demonstrate that the prepared composites are ferromagnetic and that the coercivity is 96 Oe. The magnetic carbon nanofibers can be aligned as a long-chain structure in an external magnetic field.

Preparation and characterization of nickel coated carbon fiber reinforced polycarbonate composites

Polycarbonate was reinforced with nickel coated carbon fiber and various composites were made by changing the fiber content. For comparative study, carbon fiber as such was also used to fabricate composites. Nickel coated carbon fiber was prepared by dip coating method. Scanning electron microscope studies indicated that the thickness of coating was in the rage of 1.0–1.8 µm on a 4–6 µm thick carbon fiber. Tensile and flexural properties of nickel coated carbon fiber composites were found to be higher than that of uncoated composites. Impact properties decreased with increase in fiber content in both coated and uncoated carbon fiber reinforced composites. Nickel coating decreased the notch sensitivity of composites. Significant improvement in abrasion properties were observed upon introduction of nickel coated carbon fibers. Dynamic mechanical analysis studies indicated increase in glass transition temperature with increase in nickel coated carbon fiber content. scanning electron microscope studies indicated uniform distribution of fibers. Two-step degradation was observed in air atmosphere.

Preparation and Characterization of Nickel-Coated Carbon Fibers by Electroplating

Electroplating technique was applied to coat carbon fibers with nickel. Before plating, the initial fibers were pretreated to improve the wettability in bath. The electroplating parameters were optimized to obtain high-quality nickel-coated carbon fibers, and the effects on plating were studied. The coated carbon fibers were characterized by SEM, XRD, and XPS. The coatings are uniform, smooth, bright, and adherent to carbon fibers not only along length but also along the diameter of the filaments, and mainly composed of pure nickel. Metal-carbon-oxygen bonds are present at the interface between nickel coatings and fibers, which provides the interfacial binding force. The results of performance tests showed that the nickel-coated fibers possess a good bonding strength not less than 78.5 kPa, and exhibit excellent oxidation resistance at high temperature. Compared with the initial fibers, the wettability with aluminum is also improved obviously.

Analysis of active cooling through nickel coated carbon fibers in the solidification processing of aluminum matrix composites

Solidification processing is widely used for synthesizing fiber reinforced aluminum matrix composites. Some recent studies have used cooling through reinforcing carbon fibers to obtain better control over the solidification microstructure of cast metal-matrix composites. The present study is focused on understanding the effect of active cooling and the role of nickel coating on the structure of the composite. Multiphysics analysis is conducted to simulate the composite system and obtain temperature distribution and stresses at various stages of cooling. The analysis is limited to cooling of the liquid melt and the solidification processes is not modeled. Results show that the direction of the heat flux along the fiber can reverse as the system is allowed to cool. The results show that the von-Mises stresses do not have a severe gradient in the nickel coating but the shear stress gradient is very steep. If the structure solidifies with steep heat flux gradient and high interfacial shear stresses then the nickel coating of the fibers can fail. The analysis shows that the failure of the nickel coating can occur under the effect of thermal stresses generated in the system as a result of temperature gradients.

Ni被覆炭素繊維強化Ti/Al継手の破壊挙動

Production process of titanium and aluminum joint reinforced by nickel coated carbon fiber (Ti/NiCF/Al) has been successfully developed. Although the discontinuous stress relaxation always occurred at 100±20 MPa in the stress-strain curves of fiber free Ti/Al joints, a smooth stress-strain curve was observed in the aluminum rod of the Ti/NiCF/Al joint. The fracture toughness, which was evaluated by the integrated area of the stress-strain curve of the Ti/NiCF/Al joint which underwent ductile fracture at the Al side rod, was more than two times larger than that of the fiber free joint which fractured near the joint interface. Since the nickel coated layer prevented the reaction between carbon fiber and molten metals, it mainly prevented generation of fracture near the Ti/Al joint interface. The Ti/NiCF/Al joint exhibited the high values of stiffness (dσ/dε), fracture strain and strain at tensile strength. These improvements were explained by both fining the metallic compounds and solution hardening by nickel addition, as well as the broad interface area of fine carbon fibers.

The effect of thermal treatments on the mechanical and electrical properties of nickel-coated carbon fibre composites

The effect of thermal treatments on the mechanical and electrical properties of nickel-coated carbon fibre composites Nickel-coated carbon fibre (NiCCF) composites may find technological applications within many industrial sectors, including: laptop computers, automotive and military industries. Typically, these applications require that NiCCF be subjected to extensive material processing; thus, optimization of mechanical (and electrical) properties for this material at the stage of its production is of significant importance. The present paper reports the application of specific, high-temperature heat treatments to laboratory-produced 12K50 NiCCF material, carried-out in order to improve the ductility and interfacial adhesion of electrodeposited Ni coating to the surface of carbon fibre substrate.

Optimization of nickel nanocomposite for large strain sensing applications

A novel large strain sensor has been developed using a silicone/nickel nanostrand/nickel coated carbon fiber nanocomposite system. The effect of conductive filler volume fraction on the piezoresistive response of the nanocomposite sensor has been studied in order to determine the optimal composition for use in large strain/motion sensing applications. Electromechanical testing of various compositions revealed that optimum performance was achieved using 11 vol% nickel nanostrands with 2 vol% nickel coated carbon fiber in the silicone matrix. Initial results indicate that this nanocomposite is capable of sensing strains of over 40% elongation.