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Babbitt bush is easy to cause severe adhesive wear due to unexpected journal fall. This paper aims to improve wear resistance of Babbitt bush.

A soft/hard hybrid surface mircoprofile of Babbitt alloy/steel was fabricated by a technology of laser texture combined with hot-pressing. The friction and wear performances of bare steel (steel-h), Babbitt bush on steel (steel-s) and Babbitt filled in dimples of steel (steel-hs) were conducted on a ball-on-disc tester under dry and lubricated conditions.

The results showed that wettability of steel-hs was enhanced by forming soft/hard hybrid surface. Compared with steel-s, the stability of friction coefficient curve of steel-hs was improved without increasing coefficient friction. The wear resistance of steel-hs was remarkably enhanced under dry and lubricated conditions.

The originality of this paper is as following: to improve the tribological properties and to prolong service life of steel-s, soft/hard hybrid surface of Babbitt filled in dimples of steel substrate was successfully fabricated by laser texturing combined with hot-pressing. This paper showed that the lipophilicity of steel-hs was best among those of steel-s and steel-h. Babbitt alloy as a soft filler on dimples of steel substrate improved anti-wear of steel-s remarkably. It provides a new way to fabricate Babbitt as bushing on steel substrate.

This paper aims to study different morphology Cu₆Sn₅ effect on Babbitt alloy tribological properties.

Different morphology Cu₆Sn₅ of Babbitt was conducted by different cooling modes. Bare Babbitt was marked by Babbitt-0, Babbitt modified by first cooling mode (marked by Babbitt-1) and Babbitt modified by second cooling mode (marked by Babbitt-2). The microstructure and microhardness of specimens were tested. Then, tribological properties of Babbitt-0, Babbitt-1 and Babbitt-2 were performed by reciprocating mode under lubricated condition.

The results showed that shape Cu₆Sn₅ of Babbitt was changed from mixed needle and star-like shape to short rod-like or granular shape. The microhardness of Babbitt-1 was highest than that of Babbitt-0 and Babbitt-2. Compared with Babbitt-0 and Babbitt-2, tribological properties of Babbitt-1 were better under lubricated condition due to short rod-like and sparse distribution of Cu₆Sn₅. Moreover, the simulation result of strain and stress of Babbitt-1 was lowest than that of Babbitt-0 and Babbitt-2.

Different morphology (shape and distributed) of Cu₆Sn₅ was obtained by different cooling modes. Modulated different forms of Cu₆Sn₅ around SnSb was beneficial to improve Babbitt alloy tribological properties.

The paper aims to analyze the evolution of the lubrication regime by studying the variation of friction coefficient with the rotational speed of the shaft and the impact of the applied load in the starting phase of a cylindrical journal bearing. The paper also aims to ensure that the oil layer is large enough for the rough edges of the outer layer of the bushing and the shaft cannot come into contact. The bearing is made of steel backing material and babbitted (88 per cent tin) on its inner surface.

A numerical analysis is performed taking into account the thermal effect to better predict the operating performance of a hydrodynamic plain cylindrical journal bearing during the start-up and observe the variation of the heat production in bushing inner surface. The flow is modeled based on the Reynolds equation and discretized using the finite volume method.

The evolutions of the start-up speeds of the bearing have remarkable influence on friction torque; average temperature and dissipated power increased with increasing speed and increasing load, but the maximum pressure and the eccentricity decreased with the increase of the start-up speed. The friction coefficient, minimum film thickness and attitude angle increase with elevation of start-up speed.

For the start-up speed of 750, 1,000 and 1,800 rpm and an applied load of 1,000 N, the regime of lubrication of the bearing passes the hydrodynamic regime to the mixed regime; therefore, during start-up and under heavy loads, the bearing must move very quickly at these speeds to avoid contact of the inner surface of the bearing and the shaft.

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.

VANDERVELL PRODUCTS LTD. have recently completed and opened their new factory and head‐quarters at Maidenhead, Berkshire. This plant occupies some 125,000 sq. metres and provides the company's largest production area as well as being the administrative home of the company. The Acton plant, originally the company h.q. is being phased out and production is being transferred to either Maidenhead or Tremorfa, which is a new factory in South Wales. (Tremorfa has been established for the production of pressed steel rocker arms).

Provides a brief history of Glacier Vandervell Europe. Describes the range of new materials developed, which are manufactured alongside the more traditional materials. The range includes copper lead and lead bronze, aluminium‐based materials and polymer bearings. Details further research taking place into interactions between components in the bearing system. Summarizes the testing processes at the new laboratory in Kilmarnock.

The purpose of this paper is to study the tribological effect of zinc borate ultrafine powder (ZBUP) oil additive on the running-in quality.

The running-in quality was assessed by friction coefficient and surface topography. Fractal parameters including fractal dimension, the width of multifractal, the multifractal difference, multifractal parameters, phase trajectory and correlation dimension were used to extract the nonlinear characteristics of surface topography and friction coefficient.

When the ZBUP additive was added, the convergence degree of the phase trajectory and the stability of the running in were higher than that of base oil. It indicates that the ZBUP additive can improve the running-in quality of sliding bearing. Besides, the ZBUP additive can shorten the running-in time. A boundary protective film, which has good friction-reducing and anti-wear effects, was generated on the surface when the ZBUP additive was added.

The results have a great significance to improve the running-in quality and prolong the service life of the sliding bearing.

Axle boxes have been a constant recurring source of trouble to all wagon users from earliest days. This bearing would seem to be a great stride forward in the practice of tribology, in conjunction with metallurgy and lubrication design.

It is common practice in the engineering industry to deburr newly cut gears by the lengthy process of hand filing. Recently the Elgro Machine Tool Co., a subsidiary of Gem Brushes (Luson) Ltd., London, N.W.10, has produced a machine which greatly reduces the time taken to deburr a gear.

This paper aims to investigate the fluid flow regime and the elastic effect in a plain cylindrical journal bearing subjected to highly severe operating velocity to better predict the behavior of the bearing for the turbulent flow regime.

A numerical analysis of the behavior of an elastohydrodynamic for cylindrical journal bearing finite dimension coated with antifriction material in turbulent regime, is implemented using the code-ANSYS CFX. This analysis is performed by solving the Navier–Stocks equations of continuity by the method of finite volume for rotational speeds ranging from 6,000 to 15,000 rpm, that is to say for different Reynolds number.

This study aims to better predict the elastic behavior in a journal bearing subjected to severe operating conditions. The speed of rotation varies from 6,000 to 15,000 rpm.

The results clearly show that significant pressures are applied in the extreme case of speed, that is to say to the turbulent regime. There is an emergence of new rupture zone pressure, we do not usually see the regime established; the level of the supply groove. Displacement of shaft relative to the bearing is remarkable by introducing the elastic effect and the turbulent regime.