Showing papers in "Tribology International in 1982"

TL;DR: In this article, solid lubricants, which can be used above 300°C in air, are discussed; coatings and self-lubricating composite bearing materials are also covered.

TL;DR: In this paper, it was concluded that zinc dialkyldithiophosphates decompose in oil solution predominantly by a hydrolytic mechanism, ultimately to zinc polyphosphate and a mixture of alkyl sulphides, which are the precursors of the antiwear action of zddp.

TL;DR: In this article, hole-entry bearing configurations are compared with other bearing configurations for good load support and low energy consumption, when used in any of the four modes of operation including: zero-speed hydrostatic mode, high-speed hydrodynamic mode, zero and high speed hybrid mode; and jacking mode where areas are pressurised for start-up.

TL;DR: In this paper, cylindrical test pins of some commercial polymer-based bearing materials (comprising two nylons 6, a filled nylon 6/6, a polyethene (uhmwpe) and three polyurethanes) were rotated, in dry conditions and at constant load and sliding speed, on circular tracks on stationary discs of steel gauze and abrasive paper.

TL;DR: The advantages of solid lubricants over oils and greases for the lubrication of ball bearings in spacecraft are briefly discussed in this paper, where three specific lubricants, which account for the majority of applications: ptfe-composite, rf-sputtered MoS2 and ionplated lead film, are compared in terms of durability and torque characteristics.

TL;DR: In this article, the authors compared acceleration shock pulse transducers, acoustic emission and jerk measurements from slightly damaged bearings at medium to low speeds and showed that defects at very low speeds with an acoustic emission transducer are not easily explained.

TL;DR: In this article, the wear performance of commercially available plastic-based bearing materials has been assessed in terms of the effect of bearing pressure and surface temperature rather than PV factors, and the influence of wear debris removal on the wear rate at high loads is also assessed.

TL;DR: The wear properties and bearing applications of high density and ultra-high molecular weight polyethenes (hdpe and uhmwpe) are reviewed and compared briefly with the other common basic polymers as mentioned in this paper.

TL;DR: In this article, an empirical wear equation, in the form of wear = KP a V b t c, has been determined for a variety of composites, which can also serve as tools in accelerated testing of self-lubricated bearings.

TL;DR: In this article, the performance of plain bearing applications of commercially available self-lubricating materials, including ptfe and other plastics and metals containing solid lubricants, is described and some specific applications are included.

TL;DR: A literature survey of reaction film lubrication can be found in this paper, where the state-of-the-art on reaction film Lubrication as a particular regime (compared to hydrodynamic regimes).

TL;DR: In this article, the performance of two polymer-based materials (polyimide/MoS2 and ptfe/glass fibre/S2) as self-lubricating cages for ball bearings has been comprehensively evaluated.

TL;DR: In this paper, a tri-pin-on-disc tribometer was used to determine coefficients of friction, given by some polymer-based bearing materials sliding on mild steel over a wide range of loads and speeds, both dry and lubricated.

TL;DR: In this article, the effect of nonlinear behavior on the performance characteristics of finite-width journal bearings is investigated using the Eyring model for the shear stress and shear strain rate.

TL;DR: In this paper, the needs and advantages of accelerated wear testing are discussed, with particular reference to aerospace applications, and examples are given from recent work on plastics-based dry-bearing liners to illustrate how accelerated wear tests can provide information relevant to materials selection, identification of the main parameters influencing wear and definition of the relationships between wear, material composition and structure.

TL;DR: In this article, a review of dry lubrication of spacecraft hardware is presented and some of the logic and test philosophy used in selecting and qualifying the dry lubricants presented are discussed.

TL;DR: In this article, a numerical analysis of fluid film between two faces with circumferential waviness suggests that this can provide the necessary hydrodynamic pressure generation to maintain the faces in equilibrium, separated by a continuous fluid film.

TL;DR: In this article, the friction coefficients of samples of an Al-Si-Cu alloy sliding against 52100 steel were determined on a tribometer, which represented a generic class of materials having wear resistant microstructures in which hard particles are contained within a softer metal matrix.

TL;DR: In this article, a model for mixed lubrication, assuming that the total normal load applied to the plane of the lubricated surfaces is carried partly by the hydrodynamic action of a lubrication film and partly by asperity contacts, was used to develop a numerical solution for pressure distribution.

TL;DR: In this article, it was shown that a few small protrusions or hard spot occupying an area less than 0.2% of the total contact surface can prevent the completion of running-in.

TL;DR: In this article, a model for wire drawing lubrication by soap using realistic soap rheology, plastic at low temperature, non-Newtonian viscous at high temperature, is presented.

TL;DR: In this article, a coupled Reynolds equation satisfying the pressure field in the fluid and the three-dimensional elasticity equations governing the deformations in the bearing lining are solved simultaneously using the finite element method.