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This paper aims to examine the friction and wear performance of the graphene synthesized from fruit cover plastic waste and oil palm fiber (OPF).

The graphene was synthesized by using a chemical vapor deposition method, where a copper sheet was used as the substrate. The dry sliding test was performed by using a micro ball-on-disc tribometer at various sliding speeds and applied loads.

The results show that both as-grown graphenes decrease the coefficient of friction significantly. Likewise, the wear rate is also lower at higher sliding speed and applied load. For this study, OPF is proposed as the best solid carbon source for synthesizing the graphene.

The main contribution of this study is opening a new perspective on the potentials of producing graphene from solid waste materials and its effect on the tribological performance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0486

This paper aims to investigate the tribological performance of the decanter cake feedstock biodiesel which was blended in 5 and 10 per cent volume with petroleum diesel.

The tribological performance of the decanter cake biodiesel was tested using the modified ASTM D4172 standard with temperature range from 300°C to 750°C and load range from 392 to 981 N while spindle speed is at 1,200 rpm.

At 5 per cent volume of biodiesel, friction reduced ranging from 10 to 45 per cent at all temperature and load ranges, whereas specific wear rate reduced ranging from 22 to 29 per cent at low load and 4 per cent to 15 per cent at high load for all temperature ranges. Addition up to 10 per cent volume of biodiesel reduced friction ranging from 10 to 35 per cent at all temperature and load ranges, whereas specific wear rate reduced ranging from 15 to 29 per cent only at low load for all temperature ranges.

The standardised test may not represent the actual condition of a real running diesel engine.

Because the lubricity of biodiesel was difficult to determine in a real running engine, this paper provided a standardised test for simplification.

This study aims is to investigate the correlation between tribological and mechanical properties of the fused filament fabrication 3D-printed acrylonitrile butadiene styrene (ABS) pin with different internal geometries.

The tribological properties were determined by a dry sliding test with constant test parameters, while the hardness and modulus of elasticity were determined by microhardness and compression tests.

Although the internal geometry of the pin sample slightly affects the coefficient of friction (COF) and the wear rate of the 3D-printed ABS, it was important to design a lightweight tribo-component by reducing the material used to save energy without compromising the strength of the component. The COF and wear rate values are relatively dependent on the elastic modulus. A 3D-printed ABS pin with an internal triangular flip structure was found to have the shortest run-in period and the lowest COF with high wear resistance. Abrasive wear and delamination are the predominant wear mechanisms involved.

The findings are the subject of future research under various sliding conditions by investigating the synergistic effect of sliding speeds and applied loads to validate the results of this study.

The internal structure affects the mechanical properties and release stress concentration at the contact point, resulting in hypothetically low friction and wear. This approach may also reduce the weight of the parts without scarifying or at least preserving their preceding tribological performance. Therefore, based on our knowledge, limited studies have been conducted for the application of 3D printing in tribology, and most studies focused on improving their mechanical properties rather than correlating them with tribological properties that would benefit longer product lifespans.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0143/

The purpose of this paper is to investigate the mechanisms of frictional wear stability of an activated carbon composite derived from palm kernel using phase transformation study.

The unlubricated sliding test was executed using a ball-on-disc tribometer at different loads with a constant speed, sliding distance and temperature.

Results of this paper suggest that stability of friction and wear of the test materials are primarily due to the phase transformation of the composite surface layer.

However, the effectiveness of the transfer layer as a medium for low friction and wear is only limited at certain applied loads.

This is the first study, to the authors’ knowledge, to find out the mechanisms of low frictional wear properties of an activated carbon composite derived from palm kernel using phase transformation study.

The purpose of this paper is to study the effect of hydrogen (H₂) gas on the graphene growth from fruit cover plastic waste (FCPW) and oil palm fibre (OPF), as a solid feedstock, towards the coefficient of friction (COF) properties.

Graphene film growth on copper (Cu) substrate was synthesised from FCPW and OPF, as a solid feedstock, using the chemical vapour deposition (CVD) method, at atmospheric pressure. The synthesised graphene was characterised using Raman spectroscopy, Scanning Electron Microscopy (SEM) and Electron Dispersed Spectroscopy (EDS). Surface hardness and roughness were measured using a nano-indenter and surface profilometer, respectively. Then, a dry sliding test was executed using a ball-on-disc tribometer at constant speed, sliding distance and load, with coated and uncoated copper sheet as the counter surface.

The presence of H₂ gas reduced the running-in time of the dry sliding test. However, there is no significant effect at the constant COF region, where the graphene growth from FCPW shows the lowest COF among other surfaces.

This paper is limited to graphene growth using the CVD method with selected parameters.

To the authors’ knowledge, this is the first paper on growing graphene from palm oil fiber via the CVD method and its subsequent analysis, based on friction coefficient properties.

The purpose of this study is to investigate the effect of dimple size on the tribological performances of laser surface-textured palm kernel-activated carbon-epoxy (PKAC-E) composite.

A PKAC-E disc 74 mm in diameter was fabricated using the hot compression moulding technique. Five different types of surface contacts were prepared using a CO2 laser surface-texturing machine: a non-textured surface, and surfaces with dimples between 500 and 1,200 μm in diameter. The area density, contact ratio and depth were kept constant. A sliding test was carried out using a ball-on-disc tribometer under boundary lubricated conditions with constant sliding speed, sliding distance and applied load.

In general, the results showed that the friction coefficient decreased with an increasing dimple diameter of surface-textured PKAC-E composite. However, the appropriate dimple diameter for maintaining low friction coefficient is proposed in the range of 800 to 1,000 μm.

This is the first study, to the authors’ knowledge, to investigate the effects of dimple size, which is larger than 500 μm, on the tribological performances of laser surface-textured PKAC-E composite.

This paper aims to investigate the effect of hexagonal boron nitride (hBN) nanoparticles on extreme pressure (EP) properties when used as an additive in lubricating oil.

The nano-oil was prepared by dispersing an optimal composition of 0.5 vol. per cent of 70 nm hBN in SAE 15W-40 diesel engine oil using a sonication technique. The tribological testing was performed using a four-ball tribometer according to the ASTM standard.

It was found that the nano-oil has a potential to decelerate the seizure point on the contact surfaces, where higher EP can be obtained. More adhesive wear was observed on the worn surfaces of ball bearing lubricated with SAE 15W-40 diesel engine oil as compared with the nano-oil lubrication.

The results of the experimental studies demonstrated the potential of hBN as an additive for improving the load-carrying ability of lubricating oil.