About Emerald www.emeraldinsight.comEmerald is a global publisher linking research and practice to the benefit of society. The company manages a portfolio of more than 290 journals and over 2,350 books and book series volumes, as well as providing an extensive range of online products and additional customer resources and services.Emerald is both COUNTER 4 and TRANSFER compliant. The organization is a partner of the Committee on Publication Ethics (COPE) and also works with Portico and the LOCKSS initiative for digital archive preservation. AbstractPurpose -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. Design/methodology/approach -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. Findings -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. Originality/value -The results of the experimental studies demonstrated the potential of hBN as an additive for improving the load-carrying ability of lubricating oil.

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An experimental investigation was conducted to investigate the potential of hexagonal boron nitride (hBN) nanoparticles as friction modifier and antiwear additive in engine oil. In this study, an optimal composition (0.5 vol.%) of 70 nm hBN nanoparticles was dispersed in SAE 15W-40 diesel engine oil by sonication technique. Sample was stabilized using 0.3 vol.% oleic acid as a surfactant. The tribological test was performed using a four-ball tribometer. Surface morphology and its chemical composition were carried out using a profilometer, Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray Spectroscopy (EDX). It was found that the optimized nano-oil could reduce the coefficient of friction and increase wear resistance, as compared with conventional diesel engine oil. Some adhesive and abrasive wear types were identified as predominant wear mechanisms.

Nanotechnology currently has an important role in reducing engine wear and improving fuel efficiency within engines using nanoparticle additives in engine oil. In this work, the effect of hexagonal boron nitride (hBN) and alumina (Al2O3) nanoparticle additives, on the tribological performance of SAE 15W40 diesel engine oil, was studied. A tribological test was conducted using a four-ball tribotester. The results show that the coefficient of friction (COF) and wear rate of the ball reduced significantly by dispersing hBN nanoparticle additives in SAE 15W40 diesel engine oil; compared to without or with Al2O3 nanoparticle additives. This is in accordance with the significant reduction of wear scar diameter and smoother worn surfaces observed on the balls.

This article presents the simulation analysis on the effectiveness of impact reduction control based magneto-rheological elastomer isolator device (MREID). The MREID is one of the impact isolator devices that produce controllable stiffness by controlling the input current supply to the device coil. In order to control the input current for MREID, a hybrid control structure combining the skyhook and active force control strategy (HYSAFC) is proposed. Firstly, the characteristics of MREID in squeeze mode are investigated systematically in order to establish the relationship between the supply input current to the subsequent force and impact energy within the MREID. The proposed control strategy is used for force tracking control in determining the amount of input current to be applied to the MREID. The desired input current is determined by a current generator that is developed using inverse ANFIS technique which will regulate the current amount based on the desired force and impact energy. The effectiveness of the actively controlled MREID is evaluated using MATLAB simulations by comparing the performance of the MREID controlled by skyhook control against a passive damper. It is shows that the proposed controller recorded better response compared to skyhook controller, thus improving the stability and the effectiveness in controlling the MRE isolator device.