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In this study, the dry sliding wear behaviour of plasma sprayed composite Ni-Cr coatings with nano Al2O3 particle concentrations of 0, 5, 10, 15, 20, and 100 wt.% on Al6061 substrate material was analysed. The coatings were characterised by scanning electron microscopy. The results showed higher porosity and coating thickness values for 100% and 20% nano Al2O3 particle coatings. The microhardness was found to increase with an increase in nano Al2O3 particle concentration in the Ni-Cr coating matrix. The porosity values were found to decrease with an increase in coating thickness. It is found that the specific wear rate of the Ni-Cr/15% Al2O3 particle coating is reduced by 54.02% compared to the Al2O3 particle coating. [ABSTRACT FROM AUTHOR]

In this work, the dry sliding wear characteristics of Ti6Al4V (Ti64) – EN31 (steel) tribo-pair at incremental sliding velocity (SV, 0.838–1.466 ms-1) and load (L, 50–100 N) conditions are elucidated. As evident, specific wear rate (SWR) and coefficient of friction (CoF) increases and decreases, respectively with load and SV. The wear response of Ti64 undergoes a transition from composite type (oxidative and metallic) to delamination. The evolved oxides, viz. TiO and Ti8O15 were majorly in the form of free particulates. At low SV (0.838–1.047 ms-1) and low load (50–70 N), the movable particulates can activate a separation effect limiting the damage due to wear. During severe sliding (SV = 1.257–1.466 ms-1 and L = 70–100 N), the combined influence of frictional heating instigated thermal softening, and the formation/retainment of hard-coarse particulates at the interaction zone causes perforation into the substratum, assisting in spalling. [ABSTRACT FROM AUTHOR]

This work studies the friction and the sliding wear behaviour of surface treated SAE 4140 steel. The performance of ion nitriding and PVD TiN coatings applied by means of industrial processes as single or duplex treatments was evaluated. Although the deposited TiN coatings (0.7 µm thick) resulted thinner than most of the typically employed for sliding situations, the present work shows that they can provide very good protection. The use of ion nitriding as a pretreatment proved to be beneficial when combined with such a thin coating. However, in the pin on disc sliding tests the coated discs developed the highest friction coefficients and boosted the damage in the steel pins. [ABSTRACT FROM AUTHOR]

In this work, the design of the experiment was used to study the influences of temperature, applied load, and sliding speed on the specific wear rate (SWR) of AISI 304 under a dry sliding pin on a disc experiment. It is found that the experimental SWR increased with the increase of temperature and sliding speed up to a certain value and then decreased significantly. It varied linearly with the applied load. In addition, the morphology of the worn surfaces was illustrated by scanning electron microscope (SEM) and the prospect of oxide layer formation due to friction and heat was inspected by x-ray diffraction (XRD). Furthermore, response surface methodology and analysis of variance were applied to test the significance of the variables and the acceptability of the nonlinear created model. Finally, a reasonable agreement was found between the experimental results of previous work and predicted modeling results with an average variation of 11%. [ABSTRACT FROM AUTHOR]

Recently, researchers have been attempting to enhance the mechanical and tribological characteristics of thermosetting epoxy composites by incorporating inorganic nanoparticles and ensuring their uniform distribution throughout the matrix. This study characterises ball-milled ilmenite (FeTiO 3 -size of 63 nm) and silicon dioxide (SiO 2 -size of 67.5 nm) fillers added to epoxy in proportions of 0:0, 2.5:2.5, 5:5, and 7.5:7.5% by weight. A liquid ultrasonic technique is used to blend the fillers with the epoxy, and compression moulding is used to fabricate the composite. Mechanical tests were performed based on ASTM standards. Tensile strength, tensile modulus, flexural strength, flexural modulus and elongations at break(tensile and flexural test) of 5:5 wt % are 30.54%, 12.2%, 32.22%, 28.98%,23.78% and 23.53% higher than neat sample respectively. Shore "D" hardness and Izod's impact strength are 4.65% and 98.93% higher at 5:5 wt % than neat sample respectively. Specific wear rate decreased from 2.6 × 10−11 m3/Nm (neat GFRP: 0 wt % glass fibre reinforced polymer composite) to 0.7 × 10−11 m3/Nm at 5:5 wt % filler. Nanoparticles lowered the coefficient of friction by around 16.66%, 60.42%, and 33.33% at sliding distances of 100 m for 2.5:2.5, 5:5, and 7.5:7.5 wt % respectively with the neat sample. A 5:5 wt percent resulted in 76.68% less wear volume loss than pure GFRP. Field emission scanning electron microscopy (FESEM) analysis revealed element distributions, particle size, pullout of fibers, damaged interfaces, filler dispersion, voids, wear debris, interfacial debonding, and cavities. Thus, this approach enhances GFRP composite's mechanical, tribological, and structural properties. [Display omitted] • Characterization of ball-milled ilmenite (FeTiO3) and silicon dioxide (SiO2) fillers (0:0, 2.5:2.5, 5:5, and 7.5:7.5 wt.%) blended by ultrasonic liquid process and manufactured by compression moulding. • The mechanical tests were conducted according to ASTM standards. At 5:5 wt%, GFRP composites have better tensile strength, modulus, flexural strength, elongations at break, Shore "D" hardness, and Izod's impact strength than pristine samples. • Filler-incorporated, produced composites have lower specific wear rate, coefficient of friction, and wear volume loss at 100 m sliding distance than pure GFRP composites. • Field emission scanning electron microscopy (FESEM) reveals the morphology of fractured and worn surfaces in samples. • EDS Mapping predicts the Distribution of Elements in the developed composite. [ABSTRACT FROM AUTHOR]

Nowadays, advanced plant fiber reinforced composites have captured the attention of many important manufacturing sectors such as the construction, automotive, and packaging industries. Recently, Jute fiber reinforced composites have replaced the most widely used synthetic fiber (glass, kevlar) reinforced composites in many applications. However, only few studies have been done on the tribological behavior of woven Jute fabric reinforced polypropylene composite material. In the present experimental endeavor, compression molding is used for the preparation of Jute-reinforced polypropylene composites. The effect of Jute fabric reinforcement on the resulting composite's behavior under friction was investigated. The tribological behavior was assessed with a computerized pin-on-disc wear and friction tester at an operating dry condition and different working parameters of sliding speed (1–3 m/s), applied load (10–30 N), and sliding distance (1000–3000 m). SEM has been utilized to support the discussion of the outcomes. The results revealed that, the addition of woven Jute fabric into PP matrix increases the wear resistance properties of polypropylene based composites as there was 3.5 - 45% reduction in coefficient of friction values and a decrease by 65% in the r specific wear rate on account of the incorporation of the Jute fabric as reinforcement. [ABSTRACT FROM AUTHOR]

In this study, it was aimed at investigating the wear performance of sawblade in processing of granites. In the experimentations, a computer controlled sawblade was used and the experiments were performed with the same-direction cutting mode. Specific Wear Rate (SWR, μm/m²) was selected as the criteria for sawblade wear performance. Effect of each operating variable on SWR was determined. Results showed that the SWR increased with respect to the increase in peripheral speed and traverse speed, and decreased with the increasing of cutting depth and flow rate of cooling fluid. Peripheral speed was determined as the most significant operating variables affecting the SWR. [ABSTRACT FROM AUTHOR]

Abstract: Different types of natural fiber are used to reduce the traditional fiber in composite fabrication due to their inherent properties when compared to other materials. New natural fiber reinforced composite (lantana-camara and bagasse) were fabricated with different volume fraction (10, 20, 30) and also tested experimentally with regard to their specific wear rate. To evaluate test data obtained, an experimental design method (L9), which is based on the Taguchi method, was used. By this method S/N ratio measurement and a new linear trend equation for composite also developed. From analysis of test results, it was determined that the composite prepared from bagasse fiber gives good wear resistance when compared to lantana-camara. The worn out samples also studied by using SEM. [Copyright &y& Elsevier]