Abrasive Properties Research Articles

Friction and wear properties of MoS2-based coatings sliding against Cu and Al under electric current

Abstract To obtain novel sliding electrical contact materials with good electrical conductivity and wear resistance, Ti/MoS2, Pb/MoS2 and MoS2 coatings were deposited by unbalanced magnetron sputtering system. The results showed that the friction coefficients of the coatings with current (0.5 A) sliding against Cu and Al balls decreased, and the primary cause was that more materials adhered from the coatings to the metal surfaces and the transfer films became denser under the action of the current. Due to the increase in the roughness and strengthening of the abrasive properties on the contact interfaces, the wear rates of the coatings with current were larger than those without current.

Effects of Fiber Fraction on the Mechanical and Abrasion Properties of Treated Cow Hair Fiber Reinforced Polyester Composites

Effects of Fiber Fraction on the Mechanical and Abrasion Properties of Treated Cow Hair Fiber Reinforced Polyester Composites

Influence of Particle Size and Calcination Temperature on the Abrasiveness of Garnet for Water Jet Cutting of Tough Materials

This study shows the influence of calcinations temperature and particle size of natural garnet mineral on its hardness and abrasiveness (H/A) for use in water jet cutting of tough materials. A standard commercial sample of the mineral was characterized in terms of the hardness and abrasiveness properties. The sample was sized to 4 fractions having the size of <60 um, > 60 < 100 um, > 100 < 200 um and > 200 < 250 um designated the symbols, FF, MF, MC and C respectively. Each fraction was separately heated in controlled conditions at temperatures up to 1000°C at a heating rate of 10°C/min in an electrically heated tube furnace. Soaking time at the maximum temperature was 60 minutes. Hardness and abrasiveness properties of the heat treated samples were tested to cut marble having a thickness of 30 mm. Results revealed that H/A of the garnet mineral increased by heating at temperatures up to 750°C and exhibited gradual decrease with higher temperatures up to 1000°C. Results were explained in the light of a structural irreversible metamorphism (SM) of the garnet crystals; almandine Fe2+ 3Al2Si3O12and propel Mg3Al2Si3O12. Metamorphism involved reorientation of the crystals followed by coherence to form dense grouping. At higher temperature, irreversible thermal expansion of the structure sets in. Characterization of the mineral was carried out with the help of XRD, SEM and FT-IR measurements.

Mechanosynthesis of composites in chemically non-reacting and exothermically reacting systems for magnetic abrasive media

Magnetic abrasive machining is one of the advanced finishing processes that produce a high level of surface quality of any type. The productivity of the finishing process and the quality of the treated surfaces are determined by magnetic and abrasive properties of the working media. To synthesize effective magneto abrasive composites with the size range of 1–100 μm the intensive mechanical treatment of powdered mixtures of chemically inert (Fe:SiC, Fe:B4C and Fe:diamond) and exothermically reacting (Fe2O3:Fe:Me, Me = Al, Zr) systems in high-energy planetary ball mills is performed. It is shown that the formation of composites is the result of intensive processes of grinding and deformation (mechanical alloying) as well as of the mechanically intensified redox reactions (mechanochemical synthesis) leading to the formation of abrasive particles (MexOy) in iron matrix. X-ray diffraction, scanning electron microscopy, Mossbauer spectroscopy and investigations of mechanical properties accompanied by the measurements of the abrasive activity in the finishing process of the surface polishing are used for the characterization of the as-prepared composites. The main parameters and mechanisms of the formation of the optimal structure of composites are revealed. It is demonstrated that the smallest roughness of the machined surface (Ra ~ 1 nm) is achieved in the case of using the mechanically alloyed Fe/diamond composite and the mechanosynthesized Fe/ZrO2 composite.

La doping inhibits stress production at the grain boundaries in Ni–WC coating

Ni–WC–La2O3 wear-resistant coatings are prepared by a plasma spray method on the pure iron. The microstructure and wear resistance of the coating are investigated. After La2O3 doping, the wear resistance of modified coating was enhanced significantly. The amount of coating wear was reduced by 61.9% and the friction coefficient was reduced by 35.7% because of the La2O3 content of 1.5 wt.% compared with the Ni–WC coating. La2O3 can suppress WC precipitation along the grain boundaries, and reduce the number of cracks in the substrate near the WC phase. Furthermore, the diffusion and segregation behavior of La atoms is studied by first-principle calculation. The simulation results show that La doping can increase the bonding energy between the WC particles and the Ni substrate, consequently improve the abrasion properties of the coating. The cohesive energy of the interface is the smallest when the La atoms occupies Ni atomic sites of the interface, as result a stable Ni–WC interface is formed on the interface. A Ni–La amorphous transition layer is formed on the Ni–WC interface. Its structure has rheological properties and relaxes the thermal stress of the interface, which reduces the Ni–WC interface cracking and improves the bonding strength.

Self‐cured Alkyd Resin Using Non‐Drying Avocado Seed Oil as a Material of Regenerative Resource

Self‐cured alkyd resin was synthesized from avocado seed oil (ASO) via a two way alcoholysis‐polycondensation method. The raw ASO was evaluated for its physical and chemical properties and further epoxidized, hydroxylated, and dehydrated to obtain a desaturated ASO. The fatty acids present in the raw ASO were evaluated with GC–MS while structural composition of the raw ASO, desaturated ASO and ASO based alkyd resin were evaluated with FTIR analytical technique. A surrogate kinetic model was used to approximate the acid functional group conversion in the alkyd reactor. FTIR and GC–MS results confirmed that the oil was predominantly saturated. The oil content of avocado seed is found to be 55% wt which justifies its availability as an industrial crop. The FTIR result further confirmed esterification reaction of the oil with acid anhydrides. The results of iodine values show that the unsaturation level of the oil increased significantly. The alkyd resin C produced met the requirements of standard drying test (ASTM 1640‐D) in presence of nano‐ZnO pigment at 32°C; exhibiting excellent adhesion, abrasion and chemical properties. The kinetic study further discloses that conversion (82%), viscosity (269 cP) and molecular weight average (4434 g/mol) were within the desired value in the state variable space.

Effect of (Ti, Al)N Nanostructured Arc-Coatings on Wear and Corrosion Properties of 4340 Alloy Steel.

This study utilized cathodic arc deposition technology to coat Ti-Al-N hard films on AISI 4340 alloy steel. Composition, morphology, and structure of the coatings were analyzed using EPMA, FESEM, XRD, and TEM. Both wear tests and polarization tests were conducted to determine the abrasion and corrosion properties of the steel before and after coating. The results showed that a specific (Ti, Al)N nanostructured multilayer was synthesized smoothly. The multilayer consisted of 10 nm-TiN and 15 nm-TiAlN interaction layers. The coating not only greatly reduced the friction coefficient of AISI 4340 alloy steel from 0.81 to 0.45, but also provided an effective improvement in corrosion resistance.

Research on quality improvement of the cross section cut by abrasive water jet based on secondary cutting

The cross section after abrasive water jet cutting can be roughly divided into several parts including initial zone, smooth zone, and rough zone. The surface quality of the smooth zone is high. But, the surface quality of the rough zone is very low due to the existence of striations. In addition to striations, the kerf taper is also a major defect of abrasive water jet. The defects of cutting quality greatly limit the application range and the further development of abrasive water jet machining technology. In order to improve the cross section quality of abrasive water jet cutting, four secondary cutting schemes including the positive secondary cutting, the opposite secondary cutting, the reversed positive secondary cutting, and the reversed opposite secondary cutting were proposed on the premise of not increasing cutting power (i.e., parameters such as pressure, abrasive flow rate, and abrasive particle properties remain unchanged). The cross section after secondary cutting and the cross section after single cutting were compared. The contrast results show that the opposite secondary cutting scheme is better than other methods. The secondary cutting doubles the processing time, while as we know, if the traverse speed is reduced by half, it can also increase the cutting quality at the expense of doubling the processing time. Therefore, the cross section after secondary cutting and the cross section after half-traverse-speed cutting were compared. The contrast results show that the opposite secondary cutting scheme is also more feasible than the half-traverse-speed cutting scheme.

THICKNESS DETERMINATION AND CONTROL OF FUNCTIONAL Ni–COMPOSITE ELECTRODEPOSITED COATINGS

Surface electrochemically plated with nickel and highly inert particles provides useful applications: Ni–CeO2 as chemical catalysts, high hardness Ni–CBN (cubic boron nitride) as grinding tools, among others. The plating’s inert particles – 100 mm in size – on nickel surface need to be tightly adherent and evenly dispersed; it is therefore necessary to determine and control the coating layer’s thickness corresponding to the inert particles’ size by parameters like electrical current density and time. With 40–60 nm CeO2 particle size, Ni plating thickness is 12 mm. With 60–100 mm CBN particles, Ni plating thickness is up to 60 mm. Weight and plating thickness were determined by the weight method and Faraday's law. The difference between the two methods showed the presence of inert functional particles on composite coating. EDX method and SEM image also showed the alignment as well as the distribution of particles on the coating surface. Catalytic ability of Ni–CeO2 coating and abrasive properties of Ni–CBN coating were tested by special methods, proving composite plating method useful as catalyst sand grinding metal surface.

Friction and Abrasion Properties of Rubber

Friction and Abrasion Properties of Rubber

Shape memory polymer composite coatings with enhanced mechanical and antimicrobial properties

PurposeThis paper aims to exploit shape memory polymer (SMP) composite as multifunctional coatings for protecting substrates from surface wear and bacterial. The efficiency of added nano or micro-sized particles in enhancing the properties of SMP was investigated. This study also attempts to use a low-cost and effective spraying approach to fabricate the coatings. The coatings are expected to have good conformability with the substrate and deliver multi-functional performance, such as wrinkle free, wear resistance, thermal stability and antimicrobial property.Design/methodology/approachHigh-performance SMP composite coatings or thin films were fabricated by a home-made continuous spray-deposition system. The morphologies of the coatings were studied using the scanning electron microscope and the transmission electron microscope. The abrasion properties were evaluated by Taber Abraser test, and thermo-gravimetric analysis was carried out to investigate the thermal properties of prepared composites. The antimicrobial property was determined by the inhibition zone method using E. coli. The thermally responsive shape memory effect of the resulting composites was also characterized.FindingsThe morphology analysis indicated that the nanoclay was distributed on the surface of the coating which resulted in a significant improvement of the wear property. The wear resistance of the coatings with nanoclay was improved as much as 40 per cent compared with that of the control sample. The thermo-gravimetric analysis revealed that the weight loss rate of composites with nanoclay was dropped over 40 per cent. The SMP coating with zinc oxide (ZnO) showed excellent antimicrobial effect. The shape recovery effect of SMP/nanoclay and SMP/ZnO composites can be triggered by external heating and the composites can reach a full shape recovery within 60 s.Research limitations/implicationsThis study proposed a continuous spray-deposition fabrication of SMP composite coatings, which provides a new avenue to prepare novel multi-functional coatings with low cost.Originality/valueMost studies have emphasized on the sole property of SMP composites. Herein, a novel SMP composite coating which could deliver multi-functionality such as wrinkle free, wear resistance, thermal stability and antimicrobial property was proposed.

Molar Microwear of Narrow-Headed Vole (Microtus gregalis Pall., 1779) Depending on the Feed Abrasiveness.

In the narrow-headed vole, enamel microwear of the first mandibular molar (of the protoconid and entoconid anterior enamel wall) was studied under the laboratory conditions and at the fixed feed composition. The classic parameters and the area of the enamel prism lesion were taken into account. The enamel lesion patterns caused by the tooth-tooth and tooth-food interactions have been determined. Differences were found between the voles kept on feed with different abrasive properties, as well as between the lingual and buccal conids of the first mandibular molar. In the Microtus species, the ratio of micro-lesions (pits and scratches) did not depend on the abrasive properties of the feed consumed. The extent of preservation of the enamel contour anterior edge depended on the feed composition and could be used as an indicator for indirect evaluation of the Microtus species diet.

Evaluation of mechanical and wear performance of glass/carbon fiber reinforced polymer hybrid composite

Fiber reinforced polymer composites are used in various applications due to their improved mechanical properties and lighter weight. However, these materials have inadequate wear resistance in different abrasive wear environment such as gears, bearings and rollers. Thus, the evaluation and improvement of wear properties of polymer matrix composites is necessary for structural and abrasive wear environment. In this article, the three body abrasive wear properties of glass/carbon reinforced hybrid composites are investigated with different operating conditions. The Box-Behnken Design of Experiment was used to conduct the experiments. A polynomial mathematical model has been developed through Response Surface Methodology (RSM). The model predicted optimum conditions for minimum specific wear rate of the hybrid composite ([G3C2]s) is applied load of 33N and sliding distance of 1221m. Furthermore, a confirmation test has been performed experimentally and found a good agreement between them.

Tribological properties of glass/carbon hybrid composites through inter-ply arrangement using Response Surface Methodology

Polymer-based composites are extensively used in various applications such as bearings, cams, gears, clutches, etc. due to their enhanced mechanical properties and light weight. These materials are subjected to friction and wear conditions. Hence, there is a need to study the dry wear properties of these materials. This investigation highlights the dry sliding wear properties of glass/carbon reinforced hybrid composites. In this article, three body abrasive wear properties of these composites are investigated with different operating conditions (composite hardness, sliding distance and applied load). The Box- Behnken Design of Experiment was used to conduct the experiments. A polynomial mathematical model was developed using Response Surface Methodology (RSM) to optimize the various experimental parameters to minimize the wear rate of hybrid composite. The predicted input parameters are [CGGCG]S composite, 1150m sliding distance and 33.08N applied load. In addition to that the predicted results found a close agreement with the experimental one.

Effect of grit size on the wear behavior of LM6/cenosphere composites

The abrasive wear properties of stir-cast LM6 aluminum alloy-10 wt. % cenosphere composite were tested against hard SiC abrasive paper with different grit sizes and compared with the LM6 aluminum alloy. The results show that the abrasive wear resistance of LM6/cenosphere composite is better than the LM6 aluminum alloy for low loads up to 15 N (transition load) on a pin sample. The SWR and coefficient of friction decreases with increasing load. SEM studies reveal the presence of both abrasive and adhesive wear mechanisms and from both the mechanism the abrasive wear mechanism is more prominent and dominating.

Strength properties of concrete blocks with Sand Manufacture Sludge as partial replacement to fine aggregate

The proper disposal of Sand Manufacture Sludge(SMS) from the site is a major problem faced by most of the stone crushing units. SMS when dried is in the form of a fine powder. Due to its sticky nature and time taken to dry, transporting this material is very tedious. Hence it necessitates for finding a solution for the usage at the site itself, in the form of a construction material. This study focuses on replacing M Sand with SMS for the development of concrete building blocks. The study evaluates the effectiveness of use of this waste SMS in manufacturing concrete building blocks and estimating its strength properties, keeping a constant workability throughout. The strength, impact and abrasion properties of the concrete blocks are studied and compared with the conventional blocks and shows good agreement

Effects of Aluminum Deposition on the Functional Properties of the Meta-aramid Fabrics

Meta-aramid fabrics were deposited with aluminum to examine the effects of aluminum deposition on the functional properties of meta-aramid fabrics. Various functional properties of the aluminum deposited meta-aramid fabrics were assessed with sputtering processing parameters such as chamber pressure and sputtering power. SEM-EDX was utilized to investigate surface morphology and compositions of the deposited meta-aramid fabrics. The optical, thermal, electric, and abrasive properties of the deposited meta-aramid fabrics were measured by color reader, KES-F7 thermo-Lab 2 system, milliohm meter, and abrasion testing machine. The obtained results indicated the optical, thermal, electric, and abrasive properties of the deposited meta-aramid fabrics were influenced clearly by deposition processing parameters. The light reflectance, thermal conductivity, electric resistance, and abrasion strength of the aluminum deposited meta-aramid fabrics were shown to be a maximum at a chamber pressure and a sputtering pressure, and the optimum deposit condition could be established.

Tribological and mechanical performance of sisal-filled waste carbon and glass fibre hybrid composites

Abstract This study has been carried out to show the use of natural fibres as the potential substitute of synthetic fibres in tribo-composites. The abrasive wear behaviour and mechanical properties of waste sisal/glass, sisal/carbon hybrid fibre reinforced polypropylene (PP) composites were analysed in this study. Results showed that increasing the sisal fibre weight content in the composites increases the coefficient of friction. The abrasion volume of sisal/glass hybrid composites showed significantly lower than those of sisal/carbon hybrid composite for the same hybrid ratios. This means that addition of sisal fibres on waste carbon and glass fibre reinforced PP composites decreased the potential of tribological performance. Although adding of sisal fibres as a natural substitute fibre source to waste short carbon fibre composites lead to inferior properties, an addition of sisal fibres to waste glass composites shows lower densities, comparable mechanical and abrasion volumes than that of waste glass fibre composites. This shows that sisal fibres can be used in place of glass fibres. The scanning electron micrographs of the fracture surfaces show that the wetting interaction of sisal and glass fibre with PP matrix is better than those of the sisal carbon hybrid composites. Furthermore, the worn surfaces of the sisal and its hybrid composites show vertical cracks, loose fragments, micro ploughing and transfer layers.

A research on tensile and abrasion properties of fabrics produced from conventional and fire resistant type polyester yarns

A research on tensile and abrasion properties of fabrics produced from conventional and fire resistant type polyester yarns

The Abrasive Wear Resistance of the Segmented Linear Polyurethane Elastomers Based on a Variety of Polyols as Soft Segments.

The presented results make an original contribution to the development of knowledge on the prediction and/or modeling of the abrasive wear properties of polyurethanes. A series of segmented linear polyurethane elastomers (PUR)—In which the hard segments consist of 4,4′-methylene bis(phenylisocyanate) and 1,4-butanodiol, whilst polyether, polycarbonate, or polyester polyols constitute the soft segments—Were synthesized and characterized. The hardness and wear performance as functions of the variable chemical composition of polyurethane elastomers were evaluated in order to define the relationship between studied factors. The microstructure was characterized in detail, including analysis of the hydrogen bonding by Fourier transformed infrared (FT-IR) spectroscopy and the phase structure by X-ray scattering (WAXS) and differential scanning calorimetry (DSC) methods. The presented studies provide the key features of the polymer composition affecting the abrasive resistance as well as attempts to explain the origin of the differences in the polyurethane elastomers’ performance.