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Thick composite claddings of carbides on a metal matrix are ideal for use in components that are subject to severe abrasive wear. It is a metal matrix composite (MMC) that is reinforced by an appropriate ceramic phase and nano-diamond cladding to reduce friction and to protect the opposing surface. The paper aims to discuss these issues.

This work evaluated the wear performance of carbon steel cladded with TiC/nano-diamond powders by gas tungsten arc welding (GTAW) method. The microstructures, chemical compositions, and wear characteristics of cladded surfaces were analyzed by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX).

The cladding was uniform, continuous, and almost defect-free, and particles were evenly distributed throughout the cladding layer. The results of wear test indicate that the friction coefficient of the TiC+1.5% nano-diamond cladding is lower than that of AISI 1020 carbon steel. Thus, the wear scar area of the TiC+1.5% nano-diamond cladding is only one-tenth of the AISI 1020 carbon steel.

The experiments in this study confirm that, by reducing friction and anti-wear, the cladding layer prepared using the proposed methods can prolong machinery operating life.

This paper aims to analyse the influence of the thickness of different layers [diamond-like-carbon (DLC) and chromium nitride (CrN)] on the sliding wear behaviour of a multifunctional coating on AISI 1020 substrates. When small and cheap components need to be manufactured in large scale, they are often produced using soft metals, such as unhardened low carbon steels and pure iron.

Two families, one with thicker films and the other with thinner films, were deposited onto a soft carbon steel substrate by plasma-enhanced chemical vapour deposition (PECVD). Reciprocating linear tests with incremental loading assessed the durability of the coatings. In addition, friction coefficient and wear rates of both specimens and counterbodies were measured at a constant load.

Thinner layers presented lower sliding wear rates (four-five times lower) for both specimens and counterbodies, less spalling and protective tribolayers on the wear tracks.

Although multilayered CrN–DLC coatings on relatively hard substrates such as HSS and cemented carbide tools are already a proven technology, much less is known about its deposition on a much softer substrate such as low carbon steel. In previous works, we have analysed the influence of layer thickness on hardness and scratch resistance of the same coatings. This paper presents results for their performance under wear sliding conditions using an original approach (three-dimensional triboscopic maps) for two distinct configurations (increasing load and constant load).

This paper aims to compare the wear performance of carbon steel specimens clad with TiC, WC and TiN powders by the gas tungsten arc welding (GTAW) method under optimum processing conditions.

Various ceramic powders (TiC, WC and TiN) with equal percentages by weight were prepared for use as cladding materials to compare their effects on wear resistance. The wear behaviors of different cladding specimens were evaluated with a rotating-type tribometer under dry sliding conditions. The cladding microstructures were characterized by optical microscopy, scanning electron microscopy and X-ray energy dispersive spectrometry.

The experimental results confirmed that the hardness was also much higher in the carbon steel with cladding than in carbon steel without cladding. The pin-on-disc wear test showed that the wear-resistance of ceramics clad with TiC is better than that in ceramics clad with WC or TiN. The wear scar area of the specimen with TiC cladding was only one-tenth that of carbon steel without cladding.

The experiments confirm that the cladding surfaces of ceramic particles reduce wear rate and friction.

The purpose of this paper is to test the wear behavior of a carbon steel surface after cladding by gas tungsten arc welding (GTAW) method to enhance wear resistance.

The microstructures, chemical compositions, and wear characteristics of cladded surfaces were analyzed by scanning electron microscopy (SEM), and energy dispersive X‐ray spectroscopy (EDX). A rotating‐type tribometer was used to evaluate the wear characteristics of cladded specimens under dry sliding conditions at room temperature. The dry sliding wear resistance of the coatings was tested as a function of applied load and sliding time, and wear mechanisms were elucidated by analyzing wear surfaces.

The experimental results revealed an excellent metallurgical bond between the composite coating and substrate. The coating was uniform, continuous, and almost defect‐free, and particles were evenly distributed throughout the cladding layer. Hardness was increased from 200 HV in the substrate to 650‐800 HV in the modified layer due to the presence of the hard TiC phase. The excellent wear resistance and very low load sensitivity observed in the dry sliding wear test of the intermetallic matrix composite coating were due to the high hardness of TiC and the strong atomic bonds of the intermetallic matrix.

The experiments in this study confirm that, by reducing friction and anti‐wear, the cladding layer prepared using the proposed methods can prolong machinery operating life.

The purpose of this paper is to evaluate the wear performance of carbon steel cladded with TiC powders by gas tungsten arc welding method. Because of poor wear resistance, carbon steels have limited industrial applications as tribological components.

The cladding microstructures were characterized by optical microscope, scanning electron microscope (SEM) and X-ray energy dispersive spectrometer. The wear behavior of the clad layer was studied with a block-on-ring tribometer.

The experimental results revealed that the metallurgical interface provided an excellent bond between the cladding and the carbon steel substrate. The cladding revealed no porosity or cracking, and particles were evenly distributed throughout the cladding layer. Hardness was increased from HRc 6.6 in the substrate to HRc 62 in the cladded layer due to the presence of the hard TiC phase.

The experiments confirm that the cladding surfaces of TiC particles reduce wear rate and friction. Increasing TiC contents also improves hardness and wear resistance at room temperature and under dry sliding wear conditions.

The purpose of the paper is to study effect of the implantation of oxygen and helium ions on the corrosion performance of the AISI3l6L stainless steel. It presents useful new results which allows one to draw conclusions as to the suitability of the helium and oxygen ion implanted AISI 316L stainless steel for biomedical use in the body.

The implantation of oxygen and helium ions was done on AISI 316L SS at an energy level of 100 keV at a dose of 1×10¹⁷ ions/cm², at room temperature. In order to simulate the natural tissue environment, an electrochemical test using cyclic polarization was done in a 0.9 percent sodium chloride solution at a pH value of 6.3 at 37°C. This was carried out on both the virgin and implanted AISI 316L stainless steel for the purpose of comparing performance. In addition to this, the hardness of the virgin and implanted samples was also studied using Vickers microhardness tester with varying loads. Besides, the surface morphologies of the implanted samples and the corroded samples were studied with XRD and SEM.

From the study the following findings are made. First, the XRD and SEM results were found to be in accordance with the corrosion test results. Second, the general corrosion behavior showed a significant improvement in the case of both helium implanted (icorr=0.0689 mA/cm²) and oxygen implanted (icorr=1.104 mA/cm²), when compared to the virgin AISI 316L SS (icorr=1.2187 mA/cm²). The pitting corrosion showed a significant improvement for helium implanted (Epit=230 mV) when compared to virgin material (Epit=92 mV). The oxygen implanted has not shown any improvement (Epit=92 mV). The surface hardness is found to be 1202 HV for helium implanted and 1020 HV for oxygen implanted, while it is found to be 195 HV for the virgin material. The hardness of the helium and oxygen implanted samples is found to be increased by about 600 percent and 500 percent, respectively, when compared to the virgin samples. Helium implanted samples show better performance in terms of corrosion resistance and hardness when compared to those of the oxygen implanted samples.

Although a number of authors have conducted many research on AISI 316L stainless steel, this work has original experimental results in terms of the oxygen and helium ion implantation parameters used and the specific tests: microhardness, electrochemical corrosion test, SEM and XRD that were used. It thus presents useful new results which allows one to draw conclusions as to the suitability of the Helium and Oxygen ion implanted AISI 316L stainless steel for biomedical use.

The purpose of this paper is to evaluate the protection against corrosion of carbon steel SAE 1020 promoted by a niobium- and titanium-based coating produced from a resin obtained by the Pechini method.

A resin was prepared with ammonium niobium oxalate as niobium precursor and K₂TiF₆ as titanium precursor. Carbon Steel SAE 1020 plates were dip coated in the resin and calcinated for 1 h at 600 ºC. Scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction were used to characterize the coating morphologically and structurally. Open circuit potential, electrochemical impedance spectroscopy, anodic potentiodynamic polarization and scanning vibrating electrode technique were used to evaluate the corrosion protection of the coating.

The electrochemical analyses evidence slight protection against corrosion of the coating by itself; however, the needle-like crystal structure obtained may potentially provide a good anchorage site, suggesting the coating could be used as a pretreatment that may present similar application to phosphating processes, generating lower environmental impacts.

Due to increasingly restrictive environmental laws, new environmentally friendlier surface treatments must be researched. This paper approaches this matter using a combination of niobium- and titanium-based coating, produced by a cleaner process, the Pechini method.

The purpose of this paper is to test whether TiC clad layer deposited on carbon steel by gas tungsten arc welding (GTAW) improves carbon steel substrate wear resistance.

Cladding microstructure and cladded surface hardness were tested in samples prepared under varying welding parameters. The chemical composition, microstructure and surface morphology of the cladded layer were analyzed by optical microscope, scanning electron microscopy and energy dispersive X‐ray spectroscopy. The wear behavior of the cladded layer was studied with a block‐on‐ring tribometer. Wear mechanisms in the specimens are discussed based on microscopic study of wear surface characteristics.

The experimental results revealed an excellent metallurgical bond between the composite coating and substrate. Hardness was increased from HRb 6.6 in the substrate to HRb 65 in the modified layer due to the presence of the hard TiC phase. Experimental comparison of varying welding parameters revealed that welding speed and current had the largest effect on the hardness and wear resistance of the cladded layer.

The paper shows that by using cladding techniques to improve surface properties such as resistances to wear, corrosion, and oxidation, service life can be increased, and machinery costs can be reduced.

Plasma electrolytic saturation (PES) treatments were applied on the surface of AISI H13 steel and corrosion resistance of the treated samples was investigated using electrochemical test methods. The aim was to obtain optimal corrosion resistance of the differently treated samples.

Nitrocarburized and boride layers were produced on AISI H13 steel by the means of the PES technique. Different experimental parameters during each treatment provided different microstructural and electrochemical properties. The techniques used in the present investigation included X‐ray diffraction, SEM, potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS).

The plasma electrolytic nitrocarburising coating was characterized by lower integrity than a PEB coating. All PES coated steels had a noble electrochemical behavior compared to the untreated steel. Different nano‐structures and morphologies obtained by different experimental parameters produced different electrochemical behaviors.

The results obtained in this research into PES techniques can be used wherever good corrosion resistance with the highest efficiency is required.

The speed of treatment by plasma electrolytic saturation techniques makes this method very suitable for industrial production of components.

Plasma spray coating technologies are capable of depositing a wide range of compositions without significantly heating the substrate. The objective is to characterise plasma sprayed metallic coatings on a Fe‐based superalloy.

NiCrAlY, Ni‐20Cr, Ni3Al and Stellite‐6 metallic coatings were deposited on a Fe‐based superalloy (32Ni‐21Cr‐0.3Al‐0.3Ti‐1.5Mn‐1.0Si‐0.1C‐Bal Fe) by the shrouded plasma spray process. The coatings were characterised in relation to coating thickness, porosity, microhardness and microstructure. The high temperature oxidation behaviour of the coatings was investigated in brief. The techniques used in the present investigation include metallography, XRD and SEM/EDAX.

All the coatings exhibited a lamellar structure with distinctive boundaries along with the presence of some porosity and oxide inclusions. The microhardness of the coatings was observed to vary with the distance from the coating‐substrate interface. The St‐6 coating had the maximum microhardness, whereas the lowest hardness was exhibited by the Ni3Al coating. The phases revealed by XRD of the coatings confirmed the formation of solid solutions, whereas EDAX analysis of the as‐sprayed coatings confirmed the presence of basic elements of the coating powders. So far as high temperature oxidation behaviour is concerned, all of the coatings followed the parabolic rate law and resulted in the formation of protective oxide scales on the substrate superalloy.

The plasma spray process provides the possibility of developing coatings of Ni3Al as well as commercial available NiCrAlY, Ni‐20Cr and St‐6 powders on Fe‐based superalloy Superfer 800H