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The preferable concentration of titanium carbide was optimized and added as an additive to the micro-arc oxidation electrolyte to produce a high corrosion-resistant coating on D16T aluminum alloy.

Ceramic coatings were deposited on D16T aluminum alloy by plasma electrolytic oxidation in alkaline silicate electrolytes with micron titanium carbide particle suspending at different concentrations. Influences of additive concentration on morphology, elemental and phase composition and corrosion resistance of doped PEO coatings were evaluated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and electrochemical methods, respectively.

Results revealed that suspending titanium carbide additives incorporated into ceramic coatings through discharging channels and chemically transformed into amorphous stage. The content of titanium in the doped coatings increased with the increasing concentration of suspending micron additive. Compared with the coating without particle addition, the corrosion resistance of the coating produced in 8 g/L titanium carbide suspension increased more than 20 times. The result indicated that the incorporation of titanium into the PEO coatings formed on the D16T aluminum alloy could effectively improve the corrosion resistance.

The mechanism of corporation of TiC and the mechanism of improving the corrosion resistance of the coating were proposed.

Diffusion treatments may comprise the diffusion of interstitial elements such as oxygen, nitrogen, carbon, or boron into the surface from a gaseous or molten salt bath environment, or less commonly it may consist of substitutional diffusion of a previously deposited metal coating or by packing in materials such as ferromanganese or chromium with suitable additives.

The purpose of this paper is to study, analyze and present the lubricating mechanism and tribological properties of two types of oil‐based titanium complex grease containing Polytetrafluoroethylene (PTFE).

Two types of oil‐based sebacic acid/stearic acid titanium complex greases containing PTFE additive were synthesized using 3 L reaction vessel, and the base oils including neopentyl polyol ester and mixed oil of 650SN and neopentyl polyol (1:1.8). Friction‐reduction, antiwear, and load‐carrying properties of greases were evaluated using a four‐ball tester, and their dropping point and penetration were characterized using relevant ASTM standards. Morphologies of wear scar and chemical states of typical elements on worn surfaces were characterized by means of scanning electron microscope and X‐ray photoelectron spectroscopy, respectively.

Tribological results show that titanium complex grease containing PTFE had better friction‐reduction and antiwear properties than base grease. However, PTFE could not improve the load‐carrying capacity of base grease. Moreover, a synergistic effect between deposited film and adsorptive film contributes to good tribological properties of titanium complex grease.

Such a very useful lubricating material could be used in industrial applications including steel plants, power plants, packaging, and fertilizer industries.

The lubricating mechanism of titanium complex grease containing PTFE was proposed by tribochemical analysis of worn surfaces. The mechanism should become the direction of the theoretical and applied research of grease in the future.

Current methods for the preparation of composite powder feedstock for selective laser melting (SLM) rely on costly nanoparticles or yield inconsistent powder morphology. This study aims to develop a cost-effective Ti6Al4V-carbon feedstock, which preserves the parent Ti6Al4V particle’s flowability, and produces in situ TiC-reinforced Ti6Al4V composites with superior traits.

Ti6Al4V particles were directly mixed with graphite flakes in a planetary ball mill. This composite powder feedstock was used to manufacture in situ TiC-Ti6Al4V composites using various energy densities. Relative porosity, microstructure and hardness of the composites were evaluated for different SLM processing parameters.

Homogeneously carbon-coated Ti6Al4V particles were produced by direct mixing. After SLM processing, in situ grown 100–500 nm size TiC nanoparticles were distributed within the α-martensite Ti6Al4V matrix. The formation of TiC particles refines the Ti6Al4V β grain size. Relative density varied between 96.4% and 99.5% depending on the processing parameters. Hatch distance, exposure time and point distance were all effective on relative porosity change, whereas only exposure time and point distance were effective on hardness change.

This work introduces a novel, cost-effective powder feedstock preparation method for SLM manufacture of Ti6Al4V-TiC composites. The in situ SLM composites achieved in this study have high relative density values, well-dispersed TiC nanoparticles and increased hardness. In addition, the feedstock preparation method can be readily adapted for various matrix and reinforcement materials in future studies.

Provide tribological information about the applicability of multi‐layer carbon‐chromium composite coatings to gears. Discuss the protection provided against scuffing failures, wear and the influence on gear power losses.

Several screening tests, such as Rockwell indentations, ball cratering, pin‐on‐disc and reciprocating wear tests, were performed in order to evaluate the adhesion to the substrate and the tribological performance of the carbon/chromium composite coating. Afterwards, twin‐disc tests were performed at high contact pressure and high slide‐to‐roll ratios to confirm the good adhesive and tribological properties of the coating under operating conditions similar to those found in gears. Gear tests were performed in the FZG machine in order to evaluate the anti‐scuffing performance of the carbon/chromium coating using additive free gear oils. Finally, the carbon/chromium composite coating was also applied to the gearing in a gearbox and its influence on the gearbox efficiency was analysed.

The C/Cr has got very good adhesion to the steel substrate, provides low friction coefficients between contacting solids in relative movement, gives excellent protection against scuffing and wear reduction in gears, and promotes a slight improvement of the gears efficiency.

The protection of this carbon/chromium coating against gear micro‐pitting should be investigated.

This study confirms the applicability of this coating to industrial gear applications, especially in two particular applications: severe applications involving high contact pressures and high sliding, frequent start‐ups and inefficient lubrication; and acting as tribo‐reactive material and substituting non‐biodegradable and toxic additives in environmental lubricants.

This work validates and quantifies the influence of this C/Cr multi‐layer composite coating in gear applications in terms of adhesion to the substrate, anti‐scuffing performance and efficiency.

The purpose of this paper is to prepare water‐soluble TiO₂ nanoparticles and evaluate the tribological properties as additives in water.

Nanoparticles present excellent friction‐reducing and antiwear properties as additives in base oils. However, there are seldom literatures about the nanoparticles as additives in water as yet. In this work, water‐soluble TiO₂ nanoparticles were prepared by sol‐gel method and characterized with transmission electron microscopy and selected area electron diffraction. The tribological properties as additives in water were investigated by SRV and the surface analysis by scanning electron microscope and X‐ray photon electron spectroscope.

TiO₂ nanoparticles modified with polyethylene glycol have uniform size about 10 nm and easily dissolve in water. The tribological experiments showed TiO₂ nanoparticles exhibit excellent friction‐reducing and antiwear properties.

The paper is restricted to only TiO₂ nanoparticles. Some other water‐soluble nanoparticles also should be prepared and their tribological properties investigated.

Water‐soluble TiO₂ nanoparticles could be used as water additives and improve the tribological properties.

This paper emphasises that the water‐soluble nanoparticles are prepared and could be used as water additives.

This study aims to expand the reliability and special functions of lightweight materials for high-end equipment and green manufacturing, so that it is the first such research to carry out nano-composite technology of nickel-coated carbon nanotubes (Ni-CNTs)-based titanium-zirconium chemical conversion on aluminum alloy substrate.

Corrosion behavior of various coatings was investigated using dropping corrosion test, linear polarization and electrochemical impedance spectroscopy. The results showed that the corrosion resistance of the nano-composite conversion coatings was significantly improved to compare with the conventional titanium-zirconium conversion coating. The morphology and microdomain characteristics of the nano-composite conversion coatings were characterized by SEM/eds/EPMA, which indicated that the CNT or Ni-CNTs addition promoting the integrity coverage of coatings in a short time.

Surface morphology of titanium-zirconium (Ti-Zr)/Ni-CNT specimens exhibited smooth, compact and little pores. The nano-composite conversion coatings are mainly composed of Al, O, C and Ti elements and contain a small amount of F and Zr elements, which illuminated that CNT or Ni-CNT addition could co-deposit with aluminum and titanium metal oxides.

The study of corrosion resistance of nano-composite conversion coatings and the micro-zone film-formation characteristics would be provided theoretical support for the development of basic research on surface treatment of aluminum alloys.

This paper aims to focus on the potential for substituting molybdenum‐based piston ring coatings, which are recognized as “allrounder” by other candidate metallurgies. Another purpose is the tribological interaction of molybdenum‐based and new triboactive/reactive piston ring coatings with low SAP, polymer‐ and metal‐free as well as bionotox engine oils with high‐viscosity indices.

Substoichiometric titanium dioxide composed of the Magnéli‐types phases Ti₄O₇ (∼17 per cent), Ti₅O₉ (∼66 per cent), Ti₆O₁₁ (∼17 per cent) deposited by plasma spraying, a vacuum sprayed TiO_1,93 and a plasma‐sprayed titanium‐molybdenum carbo‐nitride coated piston rings were compared to a state‐of‐the‐art molybdenum‐based piston ring. They were tribologically characterized by means of BAM and SRV tests lubed under mixed/boundary lubrication by factory fill engine oils, engine oils as blends of hydro‐carbons with esters as well as prototype engine oils based on esters and polyglycols.

Overall, the molybdenum‐ and titanium‐based ring coatings wore in the same order of magnitude. The ranking depends on the test used. The BAM test favours MKP81A (PL72) more, whereas the SRV methods favour the Ti_nO_2n−1 more. The different bionotox and low‐ash prototype engine oils with reduced additive contents displayed isoperformance regarding the tribological behaviour of common and triboreactive materials. They presented no visible weakness in wear resistance, coefficient of friction and extreme pressure properties.

The next steps have to confirm functional properties by different engine and endurance tests.

Titanium‐based piston ring coatings are overall more attractive, as they are primarily refined from titania, which is cheap and not rated at stock exchanges, and they present at least an isoperformance when compared with molybdenum‐based ring coatings.

This supplier report displays the complete methodology in order to substitute molybdenum‐ by titanium‐based piston ring coatings as well as illuminating the beneficial interaction with alternative engine oils in existing engine architectures.

The purpose of this paper is to propose and evaluate the selection of materials for the selective laser sintering (SLS) process, which is used for low-volume production in the engineering (e.g. light weight machines, architectural modelling, high performance application, manufacturing of fuel cell, etc.), medical and many others (e.g. art and hobbies, etc.) with a keen focus on meeting customer requirements.

The work starts with understanding the optimal process parameters, an appropriate consolidation mechanism to control microstructure, and selection of appropriate materials satisfying the property requirement for specific application area that leads to optimization of materials.

Fabricating the parts using optimal process parameters, appropriate consolidation mechanism and selecting the appropriate material considering the property requirement of applications can improve part characteristics, increase acceptability, sustainability, life cycle and reliability of the SLS-fabricated parts.

The newly proposed material selection system based on properties requirement of applications has been proven, especially in cases where non-experts or student need to select SLS process materials according to the property requirement of applications. The selection of materials based on property requirement of application may be used by practitioners from not only the engineering field, medical field and many others like art and hobbies but also academics who wish to select materials of SLS process for different applications.

This paper aims to provide a review of available published literature in which nanostructures are incorporated into AM printing media as an attempt to improve the properties of the final printed part. The purpose of this article is to summarize the research done to date, to highlight successes in the field, and to identify opportunities that the union of AM and nanotechnology could bring to science and technology.

Research in which metal, ceramic, and carbon nanomaterials have been incorporated into AM technologies such as stereolithography, laser sintering, fused filament fabrication, and three‐dimensional printing is presented. The results of the addition of nanomaterials into these AM processes are reviewed.

The addition of nanostructured materials into the printing media for additive manufacturing affects significantly the properties of the final parts. Challenges in the application of nanomaterials to additive manufacturing are nevertheless numerous.

Each of the AM methods described in this review has its own inherent limitations when nanoparticles are applied with the respective printing media. Overcoming these design boundaries may require the development of new instrumentation for successful AM with nanomaterials.

This review shows that there are many opportunities in the marriage of AM and nanotechnology. Promising results have been published in the application of nanomaterials and AM, yet significant work remains to fully harness their inherent potential. This paper serves the purpose to researchers to explore new nanomaterials‐based composites for additive manufacturing.