Lubricating effect

The layers in the plate-like structure of talc are Joined by very weak van der Waals forces, and therefore delamination at low shear stress is produced. The plate-like structure provides high resistivity, and low gas permeability to talc-filled polymers. Furthermore, talc has several other structure-related unique properties low abrasiveness, lubricating effect, and hydrophobic character. Hydrophobicity can be increased by surface coating with zinc stearate. 

Caterpillar IH2 determines the lubricant effect on ring sticking, ring and cylinder wear, and accumulation of piston deposits. 

Tin coatings are ductile and are able to contribute a lubricating effect in the deep drawing of steel. The presence of the thin alloy layer in flow-melted tinplate coatings does not impair this property appreciably but bright electrodeposited coatings may be less ductile than others. 

Fukui, S. and Kaneko, R., Estimation of Gas Film Lubrication Effects Beneath Sliding Bushings of Micromotors Using a Molecular Gas Film Lubrication Equation," Wear, Vol. 168,1993, pp. 175-179. 

In order to establish master curves of friction or side force coefficients, the speed range has to be low in order to avoid significant temperature rises in the contact area and, if the experiments are carried out on wet tracks, also lubrication effects. 

Generally, however, it is necessary to allow higher speeds to study the influence of temperature rises and lubrication effects in the contact area because this influences profoundly the traction capabilities of tires. 

Note that the lubrication effect due to particle collisions in liquid is significant. The liquid layer dynamics pertaining to the lubrication effect was examined by Zenit and Hunt (1999). Zhang et al. (1999) used a Lattice-Boltzmann (LB) simulation to account for a close-range particle collision effect and developed a correction factor for the drag force for close-range collisions, or the lubrication effect. Such a term has been incorporated in a 2-D simulation based on the VOF method (Li et al., 1999). Equation (36) does not consider the lubrication effect. Clearly, this is a crude assumption. However, in the three-phase flow simulation, this study is intended to simulate only the dilute solids suspension condition (ep = 0.42-3.4%) with the bubble flow time of less than 1 s starting when bubbles are introduced to the solids suspension at a prescribed ep. 

Although we made no attempt to elucidate the mechanism of friction decreases in rubbers after surface fluorination, it seems to us that apart from the substitution of H atoms to F in the polymer macromolecule, which forms a fluoropolymer on the surface, there is another phenomenon that makes a significant contribution to the friction decreases, i.e., fluorination of carbon black, which is used in rubber recipes for reinforcement. It appears that when the carbon black in the surface of the rubber is fluorinated it produces a lubricating effect, followed by blooming on the surface of the treated rubber while it is under a friction load. So, in our opinion, two effects contribute to friction decrease of carbon-filled rubbers fluorination of the rubber macromolecules and fluorination of the carbon black rubbers that do not contain carbon black show a much smaller decrease in friction after XeF2 treatment. 

Publication gravure printing inks apparently show elastic behavior at D = 105 s the modulus of shearing G is 103 Pa. This indicates that at high shear rates D, between 105 and 106 s gravure printing inks develop normal stress effects and thus show a hydrodynamic lubricating effect. These deductions are relevant to an... 

Dampproofing admixtures are formulated to affect the properties of the hardened concrete, and not those of concrete in its plastic state. In the case of materials based solely on calcium and aluminum stearates, stearic acid in solid or emulsion form, bitumens and hydrocarbon resins, there will be no effect on the properties of the plastic concrete with regard to air content, workability, mix design parameters, etc. When water-reducing admixtures or accelerators are included in the formulation, the effect on the concrete will be a function of the particular type of material used (see relevant section). The wax emulsions do appear to have an effect on the properties of the plastic concrete because of the lubrication effect of the very small... 

They are characterized by rather low tensile strengths (150-300 MNt/m ) negligible ductility, and low impact strength ( ). These materials are rather soft and readily machined. On the positive side, machinability is enhanced by the lubricating effect of the graphite. Yields (mass of casting divided by total mass of metal... 

Some of these processing aids are incorporated into the bulk of the material rather than being directly applied to the surface and are known as internal release agents. In the process of migration to the surface they have an inevitable internal lubrication effect. Most internal lubricants also have an external lubricant effect, particularly at higher concentrations because usually some material finds its way to the exterior. 

In standpipe systems, aeration from the side is often implemented to provide a lubricating effect for the solids flow. Aeration is also used in process applications to provide a stripping gas to remove undesirable gas entrained by the solid particles in the standpipe flow. With side aeration, the multiplicity of flows in the standpipe becomes much more complicated. The flow patterns of solids and gas depend not only on Ap and y but also on the aeration locations and aeration rates. For a single aeration point, the possible number of flow regimes increases to 12 [Mountziaris and Jackson, 1991]. 

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