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Yarn-based strain sensors are breaking the boundaries between flexible wearable electronics and smart clothing due to their unique functionality and weavability. The sensing strain range of most flexible strain sensors is less than its tensile range, and it is easy to exceed its sensing strain range during use, resulting in unstable performance and failure of the sensor. An effective-strain-range-controllable and wear-resistant yarn strain sensor was developed with a core-sheath braided structure with the sensing yarn as the core and the braided yarn as the shell. This design strain allows for control over the effective strain range by adjusting the core sensing yarn's pre-stretch ratio and the outer braided layer's structure. This prevents damage to the conductive network and sensor failure caused by excessive stretching during use. The sensitivity, linear sensing range, and hysteresis of the braided strain sensors are effectively adjusted by changing the braiding yarns' braiding angle and the sensing yarn's pre-stretch ratio. Additionally, the sensors' appearance and texture can be customized by changing the colour and material of the braiding yarns, allowing these sensors to integrate seamlessly with the garment and enhance their aesthetics. Furthermore, when combined with elastic fabric bands, these sensors can be attached to various parts of the human body to monitor physiological information, such as respiration and movement. The braided structure design presents a versatile strategy that could be applied to other types of strain sensors, achieving stability, durability, and aesthetics simultaneously. [ABSTRACT FROM AUTHOR]

Generally, thermal barrier and wear seriously affect flight safety by deforming or disabling the inner surface of the engine and outer surface of the vehicle of supersonic aircraft. In this study, we developed a bimetallic supported composite catalyst coating which can simultaneously eliminate the "thermal barriers" and improve the wear resistance. The bimetal-loaded composite catalysts (Pt-Cu@CeO2-Al2O3) coating was obtained by co-precipitation method. The catalytic cracking for RP-3 and wear resistance of composite catalyst coatings were evaluated via thermal cracking and friction experiments. The simulated catalytic cracking experiment results show that when n(Ce): n(Al) = 1:1, the composite catalyst exhibits the highest catalytic activity, which results from the largest specific surface area and proportion of strong acid centers. Meanwhile, under lower temperature conditions, the gas production rate of RP-3 catalytic cracking is increased by 915% (550 ℃) and 186% (600 ℃) compared with the thermal cracking. Meanwhile, the low frictional coefficient of 0.533 of the catalyst coating also indicates the satisfied wear resistance. This research provides useful information for the creation of a safer flying environment and the extension of the service life of supersonic aircraft. [ABSTRACT FROM AUTHOR]

Copyright of Paint & Coatings Industry (0253-4312) is the property of Paint & Coatings Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Distinguished from traditional vulcanized rubber, which is not reusable, thermoplastic elastomer (TPV) is a material that possesses both the excellent resilience of traditional vulcanized rubber and the recyclability of thermoplastic, and TPVs have been widely studied in both academia and industry because of their outstanding green properties. In this study, new thermoplastic elastomers based on solution polymerized styrene butadiene rubber (SSBR) and thermoplastic elastomers (SEPSs/SEBSs) were prepared by the first dynamic vulcanization process. The high slip resistance and abrasion resistance of SSBR are utilized to improve the poor slip resistance of SEPSs/SEBSs, which provides a direction for the recycling of shoe sole materials. In this paper, the effects of different ratios of the rubber/plastic phase (R/P) on the mechanical properties, rheological properties, micro-morphology, wear resistance, and anti-slip properties of SSBR/TPE TPVs are investigated. The results show that the SSBR/TPE TPVs have good mechanical properties. The tensile strength, tear strength, hardness, and resilience of the TPVs decrease slightly with an increasing R/P ratio. Still, TPVs have a tensile strength of 18.1 MPa when the ratio of R/P is 40/100, and this reaches the performance of the vulcanized rubber sole materials commonly used in the market. In addition, combined with microscopic morphology analysis (SEM), it was found that, with the increase in the R/P ratio, the size of the rubber particles gradually increased, forming a stronger crosslinking network, but the rheological properties of TPVs gradually decreased; crosslinking network enhancement led to the increase in the size of the rubber particles, and the increase in the size of rubber particles made the material in the abrasion of rubber particles fall easily, thus increasing its abrasion volume. Through dynamic mechanical analysis and anti-slip tests, when the R/P ratio was 40/100, the tan δ of TPVs at 0 °C was 0.35, which represents an ordinary vulcanized rubber sole material in the market. The viscoelasticity of TPVs increased with the increase in the R/P ratio, which improved the anti-slip performance of TPVs. SSBR/TPE TPVs are expected to be used in footwear and automotive fields due to their excellent abrasion resistance and anti-slip performance. [ABSTRACT FROM AUTHOR]

In recent years, with the development of cotton picking machinery, the mechanized picking degree of cotton has been improved. As the core component of the cotton-picking machine, the picking spindle is intertwined with the cotton in the working process. Fatigue, wear and fracture often occur during cotton picking process. At present, the domestic picking spindle is mainly imported from abroad, which is expensive. Therefore, it is necessary to carry out in-depth research on the wear-resistant protection of the ingot picking. This paper mainly introduces the common methods and research status of the wear protection of cotton-picking machine, and briefly analyzes the main problems and development trends of the wear protection technology of cotton picker picking spindle. [ABSTRACT FROM AUTHOR]

To solve the problem of short service life of a certain export railway ore gondola wagon caused by the lack of wear resistance of the internal coating of the car body and early corrosion of the wall panels, an experimental evaluation is carried out and show that the polyurea elastomer material with the advantages of long- term wear- resistant and anti- corrosion was selected to achieve a good protective effect. This paper mainly introduces the specific application scheme, technical performance, coating process and application effect of polyurea elastomer material in this vehicle model. [ABSTRACT FROM AUTHOR]

Polyimide (PI) is a special engineering plastic, widely involved in mechanical components, instruments, and petrochemicals. However, single PI material is inevitably subject to wear and tear in practice, which leads to weakened material properties. In this work, Ti3C2Tx@SiO2 was prepared to enhance the wear resistance and lubrication properties of PI by intercalating SiO2 into the interlayer of Ti3C2Tx sheets. Ti3C2Tx@SiO2/PI composites were fabricated in two steps to test the tribological performances. SiO2 particles change the form of interfacial friction from sliding to rolling, thus relieving direct friction between material and steel ball. So, the composites have a minimum COF (COF = 0.33) when the content of Ti3C2Tx@SiO2 is 0.80 wt%. Moreover, the average value of wear rate was 0.24 × 10−5 mm3/(N·m) when Ti3C2Tx@SiO2 content was 1.60 wt%, which was 91.0% lower compared to the PI matrix. During the friction process, the abrasive chips of the material migrate to the surface of the steel ball to form a transfer film, which protects the material and thus reduces the wear rate. Therefore, the hybrids Ti3C2Tx@SiO2 are effective and important wear‐resistant agents and solid lubricants to improve the wear resistance and lubricity of PI or other polymer materials. Highlights: SiO2 insert Ti3C2Tx is a key factor in changing sliding friction into rolling friction, effectively reducing the COF.The average wear rate was 91.0% lower than that of the polyimide matrix when Ti3C2Tx@SiO2 content was 1.60 wt%.The minimum COF of Ti3C2Tx@SiO2/PI composites reached 0.33 when the content of Ti3C2Tx@SiO2 was 0.80 wt%.The transfer film effectively reduces further wear of the material during friction. [ABSTRACT FROM AUTHOR]

In the present investigation an attempt was made to synthesize nano-SiC/BN-reinforced Al–Zn–Mg alloy composites by varying its weight percentage of SiC (2wt%, 4wt%, 6wt%) and maintaining 3wt% BN using the squeeze casting method and comparing it with as-cast aluminium alloy. SEM and ASTM standards are used to examine the morphology and mechanical behaviour of the synthesized aluminium alloy hybrid nanocomposite. Morphological study reveals that synthesized nanocomposites show uniform distribution of reinforcement particles without indication of residual pores. Due to the presence of Mg2Si interfaces and reduction in shrinkage effects during solidification, the density and porosity of hybrid intermixtures are increased to a minimum of 0.08% and reduced to 0.0026%. In comparison with as-cast Al–Zn–Mg alloy the hardness (28.37%), tensile strength (32.53), and yield strength (34.13%), flexural (31.25%), and impact strength (27.27%) significantly improved due to enhanced wettability between the intermixture and improved grain refinement. By increasing the proportion of strengthening particles, it was found that reducible dislocation motion was observed, resulting in an improved wear rate (26.82%) of the synthesized intermixture. [ABSTRACT FROM AUTHOR]

[Objectives] This study was conducted to develop a polyurea elastomer which can be sprayed on the surface of expanded polystyrene (EPS) floating balls, so as to improve the surface strength and service life of the floating balls. [Methods] The effects of the types and amounts of isocyanate, chain extenders and polyether polyols on the gelation rate, adhesion and wear resistance of polyurea elastomer were investigated, and it was finally determined the preparation process of polyurea elastomer using liquid isophorone diisocyanate (IPDI) and amino-terminated polyether (D2000) as the main raw materials, dimethylthiotoluene diamine (E300) as the chain extender and silica as the wear resistance modifier through two-step solution polymerization of prepolymerization and chain extension. [Results] The physical properties and chemical resistance tests of spray polyurea elastomer showed that it had good physical properties and acid and alkali resist- ance, and could meet the requirements of spraying and protection of EPS floating ball surface in marine environment. [Conclusions] Polyurea elastomer coating can improve the aging resistance, wear resistance and acid and alkali resistance of EPS floating balls, and prevent them from being fragile and floating randomly to form marine floating garbage which results in "white pollution". [ABSTRACT FROM AUTHOR]

The TC4 (Ti-6Al-4V) alloy has problems such as low material hardness, poor wear resistance, and abnormal sensitivity to adhesive wear and fretting wear. In this study, we used graphene-reinforced Ti/BN composite coatings prepared on the surface of the TC4 alloy by argon arc cladding technology. We explored the optimal content of graphene to improve its hardness and wear resistance. The physical phases and microstructures of the coatings were analyzed using an X-ray diffractometer, metallurgical microscope, and scanning electron microscope. Microhardness and wear properties of the cladding coating were measured by a Vickers hardness tester and a universal friction and wear tester. The incorporation of graphene resulted in a transformation of the reinforcing phase in the coating from TiN to Ti(N, C). The C element in the molten pool was substituted with the N element in an unending solid solution, resulting in the formation of Ti(N, C) through intermittent nucleation. As the amount of graphene in the molten pool increases, the concentration of carbon (C) also increases. This leads to the continuous growth of Ti(N, C) particles, resulting in a coarser coating structure and a decrease in coating performance. When the graphene content is 5 wt.%, the microstructure refinement of the coating is the most obvious, the microhardness is 900 HV0.2, which is 3 times higher than that of the matrix, and the wear rate is 4.9 × 10−5 mm3/(N·m), which is 4.9 times higher than that of the matrix. The wear mechanism of the coating is primarily abrasive wear with some slight adhesive wear. [ABSTRACT FROM AUTHOR]

The diamond coating was prepared on Q235 steel by adding WC micro-powder to a nickel-based filler metal during induction brazing. The effects of WC powder on the microstructure and wear resistance of the diamond coating were studied. The microstructure and wear resistance of the diamond coating were characterized by scanning electron microscopy, energy spectrum, microhardness and wear loss tests. The results show that during the brazing process, diamond and WC micro-powder form metallurgical bonds with the nickel-based brazing alloy. The WC particles contribute to dispersion strengthening and fine-grain strengthening effects in the nickel-based matrix. The Rockwell hardness of the brazing alloy with a mass fraction of 10% WC increases by 7.5% compared to that without WC. Under identical wear experimental conditions, the mass loss of the diamond coating without added WC micro-powder was 0.196 g, while the mass loss of the coating with WC micro-powder added was 0.148 g. The wear resistance of the latter increased by 24.5%.

Using Al(H2PO4)3 as binder, SiC and SiO2 as high emissivity filler, Al2O3 as wear-resistant filler and CrO3 as stabilizer, the coatings with high temperature resistance and emissivity were prepared. The emissivity, heat resistance, wear resistance, adhesion, impact resistance and heat dissipation of the coating were tested. The effects of particle size and content of the filler on the emissivity and mechanical properties of the coating were analyzed. The results show that the particle size of the raw material affects the porosity of the coating, and the porosity is the key to affect the emissivity and mechanical properties of the coating. Among various raw materials, the increase of SiC particle size is conducive to the increase of porority, while the increase of SiO2 and Al2O3 particle size will increase the coating density and reduce the porority. When the content of SiC is 16.7%, tin content of SiO2 is 1.7%, and tin content of Al2O3 is 3.3%, tin average emissivity of wavelength 3r 14 µm is greater than 0.9, the wear wear resistance reaches 3.8 L/µm, this adhesion level is 0, the impact resistance is 35 cm, and the coating sample has no cracking and don not fall off after being held at 500 °C for 6 h. At the same time, its heat dissipation capacity reaches 2 times of the ban material. [ABSTRACT FROM AUTHOR]

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The TC4 (Ti-6Al-4V) alloy has problems such as low material hardness, poor wear resistance, and abnormal sensitivity to adhesive wear and fretting wear. In this study, we used graphene-reinforced Ti/BN composite coatings prepared on the surface of the TC4 alloy by argon arc cladding technology. We explored the optimal content of graphene to improve its hardness and wear resistance. The physical phases and microstructures of the coatings were analyzed using an X-ray diffractometer, metallurgical microscope, and scanning electron microscope. Microhardness and wear properties of the cladding coating were measured by a Vickers hardness tester and a universal friction and wear tester. The incorporation of graphene resulted in a transformation of the reinforcing phase in the coating from TiN to Ti(N, C). The C element in the molten pool was substituted with the N element in an unending solid solution, resulting in the formation of Ti(N, C) through intermittent nucleation. As the amount of graphene in the molten pool increases, the concentration of carbon (C) also increases. This leads to the continuous growth of Ti(N, C) particles, resulting in a coarser coating structure and a decrease in coating performance. When the graphene content is 5 wt.%, the microstructure refinement of the coating is the most obvious, the microhardness is 900 HV0.2, which is 3 times higher than that of the matrix, and the wear rate is 4.9 × 10−5 mm3/(N·m), which is 4.9 times higher than that of the matrix. The wear mechanism of the coating is primarily abrasive wear with some slight adhesive wear.

With the aim of studying the effect of the morphology, distribution, content and hardness of carbides in Fe - Cr - C surfacing layer on the wear resistance of the layer, Fe - Cr - C surfacing layers were prepared on Q355B plates by surfacing welding. The wear resistances of Fe - Cr - C surfacing layers with different chemical compositions were compared using MLGS - 225C dry and wet rubber wheel abrasive wear tester. Moreover, the microstructures of the layers were observed by DM2700M optical microscope and EM3 - AX+ scanning electron microscope (SEM), the material compositions were analyzed by AZtecone XT energy disperse spectroscopy (EDS), and the hardness was tested by Wilson R574 Rockwell hardness tester. Results showed that the surfacing layer of 2# sample had the highest wear resistance, which was mainly attributed to the fact that the carbide content in 2# sample was the highest. Besides, the columnar and blocky primary carbides were evenly distributed in the layer and grew perpendicular to the substrate, which effectively protected the substrate and decreases the wear loss, and eventually improved the wear resistance of the surfacing layer.

The value and impact that ceramic coatings have had in the development of modern mechanical systems and protection of components exposed to harsh environments are often overlooked and understated. Modern equipment must be capable of withstanding substantial attrition, impact damage, erosion and corrosion that degrades materials across a variety of applications. Ceramic coatings enable a robust protective barrier for underlying substrates that outperforms most alternative film barrier materials (i.e. polymers, metals, glasses). In this work, a comprehensive review of modern ceramic coatings for barrier protection against mechanical wear and chemical attack is discussed in detail over a large breadth of relevant topics and case studies. This review highlights many critical aspects including various coating functionalities, design architectures, processing effects, material classes and promising future directions for engineering high-performance ceramic coating. [ABSTRACT FROM AUTHOR]

Anti-fogging is crucial to applications in harsh cold environment, for which ensuring the clear sight for people and the accuracy of certain precise instruments. Although there have been some studies on frost-resistant coatings in recent years, the duration of their anti-fogging under frost conditions is not long, and the complexity of the preparation process also makes it difficult to put them into practical use. In this paper, anti-fog coatings with good anti-fog and durability properties are prepared in a one-step process using hydroxy propyl methyl cellulose (HPMC), hydroxy ethyl cellulose (HEC), and anhydrous ferric chloride (FeCl 3) as materials. The raw materials of the coating and the preparation process are green and environmentally friendly. The light transmittance of the coated glass can exceed 90 % under the harsh fogging environment. The hydrogen-bond effects impart the anti-fogging coating durability for continuous anti-fogging under harsh environments, such as 3000 cycles fabric abrasion and one-year-long term frosting at −20 °C. The presented anti-fogging strategy can be used in daily scenarios and have great application prospects in severe cold environments. [Display omitted] • Anti-fog coating was conveniently formulated in one step. • Raw materials were green and non-polluting. • The coating was resistant to 365-day frost resistance. • The coating could withstand 3000 fabric rubs. [ABSTRACT FROM AUTHOR]

The exploration of Ni-W composite coatings with high corrosion and wear resistance is highly important for engineering applications. In this study, LDH-SLS composite nanomaterials were synthesized via hydrothermal synthesis, and Ni-W/SLS composite coatings with excellent wear and corrosion resistance were prepared via pulsed electrodeposition combined with heat treatment. The successful synthesis of LDH-SLS was confirmed by TEM, EDS, FTIR, XPS and XRD analyses. Furthermore, multipoint BET specific surface area analyses demonstrated that pore size and the specific surface area of the LDH materials were enhanced by SLS. Corrosion studies showed that the Ni-W/SLS coatings with the addition of the LDH-SLS nanomaterial had higher impedance compared to the Ni-W coatings. And the Ni-W/SLS coating can show better corrosion resistance after heat treatment at 400°C with an impedance of 2.98 ×104 Ω·cm2, which is 502.2 % higher than that of the Ni-W coating, and a corrosion current of 7.2399 ×10−7 A/cm2, which is two orders of magnitude lower than that of the Ni-W coating. Comparative analyses of coating microhardness, friction curves and average friction coefficients show that heat treatment at appropriate temperatures can significantly improve the wear resistance of Ni-W coatings. The Ni-W/SLS coatings heat treated at 400°C showed the most desirable wear resistance. This study presents a new method for producing Ni-W coatings with high corrosion and wear resistance. [Display omitted] • LDH-SLS materials were synthesised by hydrothermal synthesis and the effect of SLS on LDH materials was investigated. • The Ni-W/SLS coatings were prepared by pulsed electrodeposition, and the coatings were heat-treated at different temperatures. • Various characterisation methods such as TEM, SEM, XRD, XPS, EIS and friction tests were used for the composite coatings. • The Ni-W/SLS coatings heat-treated at 400°C showed the best corrosion and wear resistance. [ABSTRACT FROM AUTHOR]

Acrylic acid has good environmental weather resistance, water resistance, alcohol resistance, dirt resistance, and other properties. An acrylic acid dispersion with a core–shell structure was prepared and reacted with a polyisocyanate-type curing agent to prepare a waterborne polyurethane topcoat suitable for wood. The prepared two-component polyurethane topcoat was used in combination with a waterborne primer and a waterborne sealing primer and applied to Pine (Pinus strobus) boards to carry out gloss, wear resistance, and adhesion experiments. The effects of different coating amounts and spraying times on the comprehensive properties of the wood coatings were studied. The experimental results showed that when the self-made two-component polyurethane topcoat for wood was matched with the primer and the sealing primer, the coating amount of the sealing primer had little effect on improving the adhesion and wear resistance but had a significant effect on the gloss. The spraying times of the primer and the topcoat greatly impacted the adhesion, but they had no decisive impact on the improvement of the gloss. When the coating amount was 60 g/m2 for the waterborne sealing primer, 100 g/m2 for waterborne primer, and 120 g/m2 for the self-made topcoat and the coating was sprayed twice, the comprehensive performance of the obtained film on the wood was the best. This research on the preparation and coating process optimization of the two-component waterborne polyurethane coatings for wood can provide a technical basis for the application of two-component waterborne polyurethane topcoats for wood. [ABSTRACT FROM AUTHOR]

The facile and low-cost fabrication of fluorine-free superhydrophobic metal surfaces for anticorrosion remains a challenging issue. Here, we report a superhydrophobic coating based on polyacrylate/SiO2 nanoparticles/graphene oxide sheets through a simple yet environmentally friendly method. The as-prepared composite coating sprayed on metal surfaces exhibits excellent superhydrophobic and corrosion-resistant properties. Furthermore, the coating surface possesses good anti-wear performance and remains superhydrophobic after harsh abrasion tests. Prospectively, the developed non-fluorinated superhydrophobic coating opens up opportunities for the application in industrial anticorrosion field.

Medium and High entropy borides with high hardness and corrosion resistance are promising wear resistant materials. High temperature (>2000 °C) is always necessary for the densification of medium and high entropy borides. Using a mixture of 10 vol% metallic cobalt and 20 vol% SiC as additives, medium entropy (Ti,Zr,Ta)B 2 ceramics were prepared at a relatively low temperature of 1600 °C by SPS. The reduced sintering temperature is attributed to the synergistic effect of Co and SiC that wet the grain boundary and promote the interdiffusion. The prepared (Ti,Zr,Ta)B 2 obtains the microhardness of 22.54 ± 0.92 GPa, comparable with other medium entropy boride ceramics prepared at 2000 °C. The tribo-tests results of (Ti,Zr,Ta)B 2 sliding against steel suggests that the tribological performance are load dependent. As the load increases, the friction coefficient first rises and then falls at a load of 10 N, which is associated with the chemical differences of the tribofilm. The tribofilm is primarily composed of O and Fe, along with Zr, Ti and Ta oxides. The iron oxide in the tribofilm will deteriorate the tribological performance. Abrasive wear is the main wear mechanism at lower load of 1 N, while adhesive wear is the predominant wear mechanism at 10 N. • The densification temperature of medium entropy diborides was significantly reduced by introducing Co and SiC as additives. • The microhardness of (Ta, Zr, Ti)B 2 prepared at 1600 °C is comparable with other medium entropy boride ceramics prepared at 2000 °C. • The tribological performance and wear mechanism of (Ta 1/3 Ti 1/3 Zr 1/3)B 2 ceramic was studied. • As the load increases, the friction coefficient first rises and then falls at a load of 10 N, which is associated with the chemical differences of the tribofilm. • From the viewpoint of its engineering applications, boride has the advantage of high hardness and can be applied in the field of wear resistant materials. [ABSTRACT FROM AUTHOR]

In this study, a novel surface initiated polymerization (SIP) method was developed from organic‐inorganic hybrid persistent initiator coating (PIC) that embeds initiator molecules into inorganic silica sol‐gel layer. Comparing with traditional silane initiator surface that prepared by chemical vapor deposition (CVD) method, the PIC can effectively improve the mechanical stability of initiator that was able to endure ten‐thousand times of friction cycles. Besides, it allows polymer grafting from sub‐surface and so the grafted brushes, poly 3‐sulfopropyl methacrylate potassium salt (pSPMA) on the PIC were also much more wear‐resisting than those prepared by the traditional ways. More importantly, the PIC could still trigger new polymerization reaction when the grafted brushes were worn off. In addition, the PIC is universal and can be covered on different substrates including glass, metals and plastics, etc. to realize functionalization of these materials. The approach may pave technological way for the application of surface grafted polymer brushes. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the properties of TIG coatings of AISI 304 steel with SiC-reinforced NiBSi and NiBSi/SiC-X metal matrix at different rate, as well as the effect of SiC reinforcement rate on microstructure, microhardness, and wear properties of the coating layer. After the coating process, scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and x-ray diffraction technique (XRD) were conducted in order to determine microstructure, chemical composition, and phases. Microhardness and wear tests were carried out to determine wear mechanism of the coating layer, and wear surfaces were also characterized by SEM and EDS. The results showed that enhanced microhardness could be achieved with SiC reinforcement and microphotograph of microstructure showed a dendritic structure with dissolved SiC particles. Moreover, coatings of AISI 304 with SiC and NiBSi/SiC presented an excellent hardness and wear resistance. [ABSTRACT FROM AUTHOR]

As glazes are papery, there is no method capable of evaluating the surface wear resistance of glazed tiles. Thus, Taber abraser with rubber wheels and abrasive belts was employed to grind out a regular wear track. The volume of track was estimated using profilometer and its analyzing software precisely. The evaluation reliability of this method was verified using six float glasses, and the standard deviation of volume loss results could be controlled less than 10%. The appropriate operating parameters were investigated using float glasses and two types of ceramic tiles from different manufacturers. The method proposed in this work has potential of success to evaluate the surface wear resistance of ceramic tiles quantitatively and precisely. [ABSTRACT FROM AUTHOR]

An Al/APC/micro-B 4 C p hybrid composites were fabricated using the hydrothermal carbonized deposition on chips (HTCDC) process and hot extrusion process. The microstructure and mechanical properties and wear resistance of the Al/APC/micro-B 4 C p hybrid composites were characterized. APC spheres and irregular micro-B 4 C p could be observed on the Al chips surface after the HTCDC process, and the micro-B 4 C p were also coated with an APC film. Al/APC/micro-B 4 C p hybrid composites were prepared by hot extrusion from the Al chips covered with APC and micro-B 4 C p. With the increase of micro-B 4 C p content, the α-Al grain sizes of composites decrease from 18.8 µm to 12.8 µm, because the dispersed micro-B 4 C p in the composites can pin the grain boundaries, hinder the migration of grain boundaries, and inhibit the growth of recrystallized grains. The highest values were obtained when the micro-B 4 C p content was 3 wt%, and the UTS and hardness values of Al/APC/B 4 C p hybrid composites (223.66 MPa and 101.8HV) were increased by 14.07% and 24%, respectively, compared with Al/APC composite. The results of the YS calculation show that thermal mismatch strengthening is the main strengthening mechanism, followed by grain-refined strengthening, and load transfer strengthening. Because the APC of the self-lubricating effect can form a lubrication film on the wear surface during sliding, the COF and wear rate of the Al/APC composite are low. When the micro-B 4 C p is added to the matrix, the micro-B 4 C p will strip the APC film from the wear surface, so the COF increases. However, the addition of micro-B 4 C p can greatly increase the hardness of the composite, as a consequence that the wear rate of the composite material is still low(1.44 ×10−5 mm3/Nm). • A novel Al/APC/micro-B 4 C p hybrid composites is successfully produced by a HTCDC process and hot extrusion process. • The grain size of composites decrease due to the increase in recrystallization nucleation and the generation of grain boundary pinning effects. • For a micro-B 4 C p content of 3%, the Al/APC/micro-B 4 C p hybrid composites shows the highest strength and hardness of 223.6MPa and 101.8HV, respectively. • The wear rate for the composites decreased, because the hardness of the composites increased and an APC lubricating film formed on the wear surfaces. [ABSTRACT FROM AUTHOR]

• A ternary solid lubricants SiO 2 /Ti 3 C 2 /PTFE was prepared by solution dispersion. • The minimum wear rate of STP/PI composites was only 0.18 × 10−5 mm3/(N·m) when the solid lubricants content was 2.0 wt%. • The minimum COF of STP/PI composites reached 0.29 when solid lubricants content was 2.0 wt%. • The SiO 2 /Ti 3 C 2 /PTFE solid lubricants favors the formation of transfer film to protect polyimide from friction. Polyimide is widely used in aerospace, electronics and electrical appliances, automotive, chemical and other fields due to its high temperature stability, excellent mechanical properties. However, polymer materials are often subjected to severe wear and tear under complex operating conditions due to their poor lubrication performance. Therefore, the improvement of lubrication performance is a key strategy to extend the service life of polyimide. Herein, a ternary solid lubricant SiO 2 /Ti 3 C 2 /PTFE (STP) is innovatively prepared by solution dispersion for reducing the friction of polyimide to increase the lubricity. Specifically, SiO 2 and PTFE are intercalated accordion-like Ti 3 C 2 nanosheets, thereby causing the nanosheets to slide relative to each other under external frictional stress. Then, STP was introduced into polyimide to prepare the ultra-wear-resistant and self-lubricating composites by blending. The results of the study showed that the STP significantly enhanced the lubrication properties of the composites, the lowest coefficient of friction (0.29) of the composites is 22.81 % lower than that of the polyimide. In addition, the inclusion of hybrids helps to form a transfer film, which effectively improves the abrasion performance of polyimide, and the lowest wear rate (0.18 × 10−5 mm3/(N·m)) was 93.35 % lower than that of polyimide. [Display omitted] Ternary solid lubricant STP effectively enhances the lubrication characteristics of polyimide and reduces wear rate. [ABSTRACT FROM AUTHOR]

Electron beam surface melting has been applied as a posttreatment to plasma-transferred, arc-deposited Stellite 6 hardfacing and its molybdenum-alloyed version. Molybdenum addition increased the surface-related properties—that is, hardness and wear resistance—via enriching the microstructure with carbides. Application of electron beam surface melting caused a further increment in hardness and wear resistance of the molybdenum-alloyed hardfacing by encouraging hypereutectic solidification to form a network of carbides surrounding the cobalt matrix. However, electron beam surface melting of the unalloyed hardfacing, which favored individual precipitation of fine carbides in the microstructure, decreased the wear resistance in contrast to the hardness. [ABSTRACT FROM AUTHOR]

Iron-based coatings with high wear resistance were prepared on a 65Mn substrate using a laser cladding technique. The coatings were characterized and compared with the substrate in terms of microstructure, phase composition, hardness distribution and friction-wear properties. The coatings had a gradient microstructure consisting of a working layer and a transition layer with different compositions. The working layer contained (Cr, Fe) 7 C 3 carbides as the hard phase, which improved the hardness and wear resistance of the coatings. The transition layer had a higher soft phase amount due to the higher Ni content, which enhanced the bonding strength between the coating and the substrate. The coatings showed a uniform and dense surface morphology, free of cracks and pores, and a fine and uniform grain size. The average hardness of the coatings was 721 HV1, which is more than three times that of the substrate. The friction coefficient and wear loss of the coatings were 0.42 and 0.0018 mg/m, respectively, lower than those of the substrate (0.48 and 0.036 mg/m). The coatings demonstrated excellent wear resistance and durability in soil tank tests, exhibiting an 81.15 % reduction in mass loss when utilized on rotary tiller blades. The results present an effective method for surface modification of agricultural machinery components and provide valuable insights for the further development of unique gradient coatings. • Iron-based gradient coatings with high wear resistance were prepared by laser cladding on 65Mn steel substrate • Coatings had a gradient microstructure with (Cr, Fe) 7 C 3 carbides as hard phase and Ni-based solid solution as soft phase • Coatings showed superior performance in soil tank tests, reducing mass loss by 81.15% compared to the original blade • Study provides a novel and effective method for surface modification of agricultural machinery components [ABSTRACT FROM AUTHOR]

Cobalt-boride (Co-B) alloys, as promising wear resistant materials, can form different intermetallic compounds. In this work, supercooling treatment is applied to control the microstructures and compounds in the alloys, and the related mechanical and tribological properties have been investigated systematically. The results suggest that besides FCC-Co and HCP-Co, it forms Co 3 B and minor Co 2 B in the as-cast samples, Co 3 B, Co 2 B and Co 23 B 6 under different supercooling degree. Tribological experiments of these alloys under distilled water environment demonstrate that the Co-B alloy containing Co 23 B 6 has the best tribological performance, followed by Co 2 B and Co 3 B. The coefficient of friction and wear rate of alloy containing Co 23 B 6 are about 0.2 and 1.6 × 10−6 mm3/Nm, respectively, which are reduced by 60 % and one magnitude lower compared to the as-cast sample containing Co 2 B and Co 3 B. The promising tribological result of Co 23 B 6 is attributed to the formation of tribolayer, which is rich in Co(OH) 2 , silicate, SiO 2 and possibly H 3 BO 3. This work provides guideline for tuning phases of Co-B alloys when using as rubbing parts in moisture environment. [ABSTRACT FROM AUTHOR]

Sensitisation to immunologically active elements like chromium, cobalt or nickel and debris particle due to wear are serious problems for patients with metallic implants. We tested the approach of using a hard and thick ceramic coating as a wear-resistant protection of titanium implants, avoiding those sensitisation and foreign body problems. We showed that the process parameters strongly influence the coating porosity and, as a consequence, also its hardness.

Graphical abstract Highlights • A new method is proposed to obtain wear-resistant hydrophobic surfaces. • The influences of different laser parameters on the wetting behaviors of water are investigated. • The structural hierarchy is essential for a robust superhydrophobic surface. • The mechanism of wear-resistant hydrophobic surfaces is analyzed. • This facile and low-cost method to produce wear-resistant surfaces can easily be extended to metal and nonmetal materials. Abstract In this study, a novel facile method, namely liquid-phase laser ablation, was proposed to obtain a robust hydrophobic surface. The cemented carbide sample was immersed in a fluorosilane solution and ablated by laser, while controlling the distance between the top surface of sample and liquid level. Then, a surface with good hydrophobicity could be obtained by one step using this technique. The effect of different laser processing parameters on the wettability of the sample surface was studied, and the water contact-angle (WCA) and the rolling angle (RA) could reach 148.4° ± 0.6°, 4.5° ± 0.5°, respectively, which indicated excellent hydrophobicity. Moreover, we found that the hydrophobic surface fabricated by the new method was more wear-resistant than that obtained by the laser texture and fluorination treatment. The hydrophobic surface exhibited excellent mechanical abrasion resistance as it maintained hydrophobicity even after being subjected to mechanical abrasion by hand-polishing 600 times with 1200 grit metallographic sandpaper. Moreover, the mechanism of wear-resistant was analyzed, which was attributed to the formation of the self-healing hydrophobic coatings with a certain thickness on the microstructures. This facile and low-cost method can not only be easily extended to other materials but also produce hydrophobic surfaces with robustness and self-healing properties. [ABSTRACT FROM AUTHOR]

Coatings were obtained in electrolytes with different phosphorus source by Plasma Electrolytic Oxidation (PEO). Anatase phase (TiO 2 ) is the main crystalline phase and rutile phase is in a minor proportion in coatings. Electrolyte with metasilicate of sodium as additive generates micro-discharges of higher size and intensity during PEO process, increasing the amount of rutile in the coating. Coatings improve wear behavior of substrate. Under the lubricated condition in Simulated Body Fluid (SBF), the formation of an amorphous layer of apatite during lubricated wear test improves the performance of coatings, allowing to slide a higher distance (100 m of sliding distance) without a significant wear in the coating against the unlubricated condition (15 m). [ABSTRACT FROM AUTHOR]

Superhydrophobic self-cleaning and wear-resistant nanocomposite surfaces were produced by mimicking the hierarchical structure of the lotus leaf using a combination of rapid self-assembly and a UV nano-imprint lithography (UVNIL) process with a silicone master. Two different acrylate formulations containing acrylated silica nanoparticles and an acrylated silicone surfactant were used. The presence of the silicone master did not suppress the spontaneous migration of the surfactant to the polymer surface, which increased its hydrophobic character. Adding acrylated silica particles considerably increased the viscosity of the acrylate suspensions and led to a shear-thinning behavior. However the particles did not prevent the fast migration process of the surfactant and further increased the hydrophobicity of the material, due to increased nanoscale roughness of the nanocomposite surface. The largest increase of hydrophobicity was achieved for the UVNIL printed lotus surfaces using the acrylate formulation with lowest viscosity. These surfaces became superhydrophobic for the highest investigated concentration of silica. These nanocomposite lotus surfaces were, in addition, very hard with a microhardness above 400 MPa and particularly wear-resistant, and were self-cleaning with respect to hydrophobic contamination. [ABSTRACT FROM AUTHOR]

Decreasing of friction coefficient by lubrication is an effective way to reduce the wear of interacting surfaces, however, use of conventional lubricants faces problems in extreme environments (e.g. outer space). The use of solid lubricants (e.g. molybdenum disulfide) as solid coatings, or as components of coating systems based on non triboactive matrix (e.g. oxides) can be solution. In this work, aluminum oxide ceramic coating containing dispersed molybdenum disulfide particles was formed on the substrates using sol-gel technique. Molybdenum disulfide (MoS 2 ) powder was suspended in alumina sol and deposited by dip-coating method on the surface of 7075 Al alloy and Si wafer. The densification of coating was made during heat treatment of substrate alloy. Prepared coatings were investigated in terms of morphology, chemical composition, crystalline structure and basic tribological properties. Morphology study of the obtained coatings revealed that their nanocomposite structure consisted of MoS 2 particles uniformly dispersed in aluminum oxide matrix. The coatings were homogeneous and free of cracks. EDS and GIXRD study proved high MoS 2 content within coatings. Tribological investigations carried out under low humidity conditions showed very low friction coefficient of coatings against Al 2 O 3 counterspecimen. The interaction of MoS 2 particles with aluminum oxide matrix was simulated using the SCiGRESS software. The conducted analysis showed that the dispersed MoS 2 could be incorporated into the amorphous structure of aluminum oxide both by physical and chemical bonding. Obtained results indicate the potential use of MoS 2 containing nanocomposite coating in contact nodes operating under outer space conditions. [ABSTRACT FROM AUTHOR]

In this study, pyrolysis carbon black (CBp) was pre-treated by the combination of air jet milling and Ar plasma technology to obtain the reinforcing filler, MP-CBp. The modification effect was verified by XPS, Raman spectroscopy and TEM images. The increment of introduced activation groups and the augmentation of surface area conferred MP-CBp an impressive reinforcement to natural rubber (NR) matrix. The excellent reinforcement of MP-CBp was attributed to the formation of strong filler network according to the mechanical properties. Besides, the tribological studies conducted under various load conditions revealed that the NR component filled with MP-CBp presented intensively improvement on the ground traction and the wear resistance. The addition of 60 phr MP-CBp intensified 20% dry traction, 33.3% wet traction and decreased 27.7% specific wear rate of NR vulcanizates. This strategy to modify CBp with cleanliness Ar plasma technique provides novel insights into not only the surface treatment of CBp, but also the manufacture of sustainable wear-resistant tire materials, which can tremendously promote the recycled utilization of waste tires. [Display omitted] • Recycling and reuse of solid products from end-of-life tires (ELTs). • Cleanliness plasma treatment of CBp for improving its matrix compatibility and dispersion. • Manufacture of wear resistant recycling tire materials. • Excellent traction and anti-wear property under both dry and wet condition of sustainable tire materials. [ABSTRACT FROM AUTHOR]