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Phosphating mild steel causes the surface to be etched into a network of microscopic channels 0.0004 to 0.0008 in. deep, the phosphate crystals being located on the intervening high spots. With this type of surface, running‐in is both rapid and safe and low friction conditions are soon established. The phosphate crystals do not act as a solid lubricant in the same sense as graphite or M0S2; initial friction is higher and final friction is much lower. Friction of MoS2, for example decreases with rubbing by a factor of 4, from 0.2 to 0.05, whereas the friction of phosphated steel decreased by a factor of 60, from 0.3 to 0.005. In addition, the final friction of the run‐in phosphated surface depended on temperature and pressure in a manner characteristic of ‘thin film’ fluid lubrication, not ‘boundary’ or ‘solid’ lubrication.

In Part 1 the authors dealt with the background of tribology and its intended purpose, ie to conserve energy by minimization of wear and friction in moving parts of plant and machinery — the basis of the 1966 Jost Report. In Part 2 they set out to show in great detail how this may be achieved dramatically by intensive research and development.

The National Engineering Laboratory is one of the larger stations of the British Government's Department of Scientific and Industrial Research. Current programmes include theoretical and experimental studies of non‐Newtonian lubricants, the development of new methods of measuring the compressibility of hydraulic fluids, research into the behaviour of oils under hydrostatic tension, and investigations of various aspects of the phenomenon of aeration in hydraulic fluids. The Laboratory's facilities for carrying out sponsored research and testing in this field are briefly described.

The purpose of this paper is to establish a rapid and effective numerical model of thin film lubrication with clear physical conception, in which viscosity variation along the direction of film thickness was used instead of average viscosity, and continuous Reynolds equation was used in the calculation of thin film lubrication.

Based on rheology and thin film lubrication with point contact and considering features of shear thinning and like-solidification of lubricant oil in the thin film lubrication state, a modified formula with overall average equivalent viscosity was proposed by combining numerical calculation and experiment data.

It is a fast and efficient method for film lubrication state simulation.

Thin film lubrication research on a nanoscale is very popular, and a variety of thin film lubrication models are proposed. Due to the complexity of thin film lubrication, it is still in the stage of revealing law and establishing calculation model.

The key issue is how to obtain the viscosity correction formula derived from engineering practice, also considered the lubricating oil class solidification and shear-thinning properties on thin film lubrication, while based on the system experiment, the viscosity modified formula for the gap, speed changes are proposed to obtain the overall average equivalent viscosity which makes the thin film lubrication micro to macro, so that a clear physical meaning for thin-film lubrication numerical calculation model is established.

Plant failures are often not fully investigated, owing to the pressures of restoring production so as to avoid delays and consequent losses. Instead, problems are overcome by quick solutions. Such solutions, however, may not eliminate the underlying cause of trouble and additional costly failures may occur.

The purpose of this paper is to investigate the rheological characteristics of graphene nanoplatelets (GNPs) and hybridized nanocomposite consisting of multi-walled carbon nanotubes (MWCNTs) and GNPs as an additive on lithium-based grease. The experiments of nanogrease are examined in different values of shear stress, apparent viscosity, temperature and shear rate using Brookfield Programmable Rheometer DV-III ULTRA and characterized by high-resolution transmission electron microscope (HRTEM) and X-ray diffraction (XRD).

First, GNPs was mixed well with lithium grease using mechanical stirring at 3,500 rpm for 15 min at room temperature to form a homogenous composite at different concentrations (0.5, 1, 1.5, 2 and 2.5 Wt.%). Afterwards, MWCNTs and GNPs are mixed and dispersed well in the lithium grease using a sonication path for 30 min and mechanical stirring at 3,500 rpm for 15 min at 28°C to form a homogenous nanocomposite.

The results indicated that 1 Wt.% of GNPs is the optimum concentration. Subsequently, the weight percentage of additives varying between MWCNTs and GNPs are tested, and the result indicate that the grease containing GNPs had a 75 per cent increase in shear stress and 93.7 per cent increase in apparent viscosity over ordinary grease.

This work describes the inexpensive and simple fabrication of nanogrease for improving properties of lubricants, which improve power efficiency and extend lifetimes of mechanical equipment.

Traditional simulation research of geological and similar engineering models, such as landslides or other natural disaster scenarios, usually focuses on the change of stress and the state of the model before and after destruction. However, the transition of the inner change is usually invisible. To optimize and make models more intelligent, this paper aims to propose a perceptible design to detect the internal temperature change transformed by other energy versions like stress or torsion.

In this paper, micron diamond particles were embedded in 3D printed geopolymers as a potential thermal sensor material to detect the inner heat change. The authors use synthetic micron diamond powder to reinforced the anti-corrosion properties and thermal conductivity of geopolymer and apply this novel geopolymer slurry in the direct ink writing (DIW) technique.

As a result, the addition of micron diamond powder can greatly influence the rheology of geopolymer slurry and make the geopolymer slurry extrudable and suitable for DIW by reducing the slope of the viscosity of this inorganic colloid. The heat transfer coefficient of the micron diamond (15 Wt.%)/geopolymer was 50% higher than the pure geopolymer, which could be detected by the infrared thermal imager. Besides, the addition of diamond particles also increased the porous rates of geopolymer.

In conclusion, DIW slurry deposition of micron diamond-embedded geopolymer (MDG) composites could be used to manufacture the multi-functional geological model for thermal imaging and defect detection, which need the characteristic of lightweight, isolation, heat transfer and wave absorption.

Samuel Denison & Son Ltd., of Moor Road, Leeds 10, have extended their range of testing machines to cover the field of research into lubrication, friction and wear. The first machine in this series is the model T62 Pin and Disc machine intended for continuous motion studies on lubricants and material combinations. The machine is illustrated.