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During tactile perception, the electrical system in the brain will respond to the changes in vibration, friction, and surface properties between the perceived surface and human skin. To establish t...

With the aim to investigate repeated braking of organic–metal brake pairs, tribological and scanning electron microscopy (SEM) experiments were performed to reveal the influence of a magnetic field on the tribological performance of brakes. A nonasbestos copper-based brake pad and gray cast iron brake disc were selected as the brake pair. The X-DM pad-on-disc friction tester was improved to set up a tribological tester under a magnetic field. The worn surfaces were observed by SEM to reveal the friction mechanisms. It was found that a magnetic field can ameliorate the dynamic friction and wear. In addition, the global mean friction coefficient increases and the wear resistance of brake materials improves. A magnetic field promotes surface oxidation and aggravates the surface heat emission condition. As a result, the mean temperature on the friction surface increases obviously. An appropriate magnetic field can improve the dynamic temperature rise and decrease the global temperature rise on the fri...

By adding magnetic powders into matrix material, it has been proved to be a creative approach to improve tribological properties of brake materials. In this paper, a novel magnetic brake material with Nd–Fe–B and nano-Fe3O4 was developed, and the influential mechanism of these two magnetic powders and their content on the friction and wear performance was deeply discussed. Firstly, some experiments were carried out to investigate the tribological performance and influential mechanisms of four groups of brake pad samples with different magnetic powders. Furthermore, based on these results, further experiments for investigating the influence that Nd–Fe–B contents have on the tribological properties were conducted. According to the theoretical analysis about experiments, it was concluded that nano-Fe3O4 is beneficial to promote the formation of friction film and has certain lubricant effects. However, Nd–Fe–B has double effects on the formation of friction film. It will have positive effects when its...

Surface texturing has been recognized as a feasible method of surface engineering to improve the lubrication properties of mechanical components. This work focuses on the hydrodynamic lubrication properties of the textured surface with asymmetric microdimples. The validity of the Reynolds equation in asymmetric microdimples is discussed based on theoretical analysis and numerical simulation. The effects of modified Reynolds number, motion directions, and parameters of the microdimple profile are investigated. The following results were obtained: Firstly, the Reynolds equation is invalid under almost all of the general conditions used in experiments and industries. Secondly, the ultimate load-carrying capacity can be taken as a new characteristic parameter to assess the lubrication property of a textured surface. Thirdly, the motion directions have a great effect on the lubrication properties. The positive motion can generate more stable load capacity under all of the modified Reynolds numbers employed, ev...

Surface texturing has been recognized to be very efficient in modifying the tribological performances of sliding surfaces. In the present article, a three-dimensional hydrodynamic lubrication model of the incompressible Newtonian fluid is proposed on the textured surface with a single spherical cap microdimple based on the full Navier-Stokes equation. The three-dimensional pressure field and velocity field of lubrication film are obtained by employing the finite volume method (FVM). The effects of geometric parameters and Reynolds number on pressure field, load-carrying capacity, friction force, and friction coefficient are investigated. Numerical simulation led the authors to conclude that the load-carrying capacity of the lubrication film is monotonously enhanced with increasing microdimple width and Reynolds number, and a reverse tendency is obtained for friction force and friction coefficient. The dimensionless optimum microdimple depth increases with the increase of the width and decreases with the i...

Two-axle vibrating screen is a widely used piece of equipment. However, its noise is high and very difficult to control. In order to design low-noise vibrating screen, the noise sources of the vibrating screen and its noise characteristics have been analyzed. The low noise material and machine components, such as low-noise compound damping plates, low-noise elastic web gears, and low-noise sieve plates have been developed, and a series of vibration- and noise-reduction techniques have been adopted. The novel ZS2065LN low-noise vibrating screen has been successfully developed. The whole developing process of the ZS2065LN low-noise vibrating screen is discussed in this article.