In the present investigation, a semi analytic and semi Numerical solution of the hydromagnetic squeeze film between anisotropic porous rectangular plates with lubricant additives has been studied. The effect of transverse magnetic field with the lubricants containing additives has been modelled as Stokes couple stress fluid. The more realistic Beavers-Joseph slip boundary conditions are used to derive the most general form of MHD-Reynolds equation, which accounts for the effects due to the lubricant additives and anisotropic nature of the porous material in the presence of transverse magnetic field. The current work aims to achieve better tribological designing for the design engineers to bring in enhanced load carrying capacity and reduced squeeze film time by the application of transverse magnetic field as compared to non-magnetic case and Newtonian case.

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Biodiesel serves as the best alternative candidate to diesel fuel for diesel engines as a result of its ability to function as substitute to meet with the rising energy demand. Biodiesel is considered more environmentally friendly than fossil fuel because it is made from renewable resources and has lower emissions. This paper focuses on the tribocorrosion behaviour of biodiesel followed by development of tribocorrosion model with the aim of understanding the combined effects of tribology and corrosion (synergism) for automotive tribo-component materials under biodiesel. A systematic review analysis was performed on tribology and corrosion test analysis for different biodiesel feedstock and factors affecting tribocorrosion system. Established theoretical model has been developed to evaluate the corrosive wear of materials with a well-controlled experimental laboratory set up as proposed. This review proffers an insight into the interactions of electrochemical and mechanical conditions of the different parameters, which govern the behavior of tribocorrosion systems. The emergence of the combined study on tribocorrosion for automotive component parts provides a methodological study to evaluate the combined behaviour based on the mechanical and synergistic effect occurring simultaneously on the automotive material in biodiesel. It was found from the study that synergism of wear and corrosion play an important role on the performance of biodiesel. Finally, it is expected that the theoretical model and proposed model set up for biodiesel biocompatible with automotive engine component materials will enhance the reliability and performance.

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In the present paper the effect of micropolar squeeze film lubrication between a cylinder and a poroelastic flat plate is presented. The synovial fluid is modeled as the micropolar fluid and the articular cartilage is considered to be a poroelastic in nature. The modified averaged Reynolds equation accounting for the randomized surface roughness structure as well as elastic nature of articular cartilage with micropolar fluid as lubricant is derived. The Christensen stochastic theory for rough surfaces is used to study the effect of two types of one dimensional surface roughness on the squeeze film characteristics of a cylinder and a rough poroelastic flat plate with micropolar fluid. Results are presented for the performance of the synovial joint with the experimentally validated values of the cartilage elasticity and permeability. It is observed that, the transverse roughness pattern improves the squeeze film characteristics whereas the squeeze film bearing performance is affected due to the presence of one-dimensional longitudinal surface roughness. These effects are more pronounced for the micropolar fluids.

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The Japanese Society of Tribologists is pleased to announce that the 2012 Paper Award of Tribology Online was awarded to:


“Friction and Wear of Ferrous Materials in a Hydrogen Gas Environment,” by Kanao Fukuda, Masaaki Hashimoto, Joichi Sugimura, Vol. 6, No. 2 (2011) 142-147.


and


“The Effects of UV Irradiation on Z-Tetraol Boundary Lubricant,” by Robert J. Waltman, John Newman, Xing-Cai Guo, John Burns, Connie Wiita, Mina Amo, Vol. 7, No. 2 (2012) 70-80.


The Award Medals were presented to the authors by Prof. Masabumi Masuko, the President of the Japanese Society of Tribologists, at the JAST Annual Meeting on 21st May, 2013.


The Paper Award of Tribology Online is given annually to the author(s), either the JAST members or non-members, of the paper(s) judged as the best paper(s) published in Tribology Online (TROL) for the previous three years. All papers that appeared in TROL for the three years are reviewed by the JAST Awards Committee.

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