| Wear resistance extensively exists in the actual production and our life. Abrasion is one of the three kinds of main reasons (abrasion, corrosion, fatigue) of invalidation of metal parts. According to incomplete statistics, about 1/3 or 1/2 of the consumption of the energy is caused by friction and abrasion. About 80% invalidation of components is caused by abrasion for materials. Abrasion not only consumes the energy and materials and decreases the equipment efficiency, but also accelerates the equipments discard and causes the parts replacement frequently and big economy loss. Therefore, abrasion is causing more and more extensive academic attention of many fields. In the process of gear driving, its main invalidation form is abrasion. The abrasion on the gear root is bigger, especially for the driving gears of ball mill, the driving gears of power plant, which have big modulus. These gears are very big, and it is complicated to be manufactured. To replace such a gear need RMB100,000, even than RMB100,000, which leads to enormous economy loss for the enterprise and society. Therefore, a new and valid method of improving anti-wear ability and carrying capacity is required, which is the key research content in the paper. The research works are as follows: 1. To study the gear surface based on the reverse engineering. 3D measurement of gear surface was completed with 3D SCANNER laser scanner. Considering the difficulty of scanning the whole parts and the structural symmetry of gear, the partial scanning of gear was done. The data point cloud was processed with Surface software, and the noise was deleted with the artificial method. The good gear model in the deleted data point cloud was selected as research object, and was made up a curve surface to form a curve surface model, then the function of mirror image was used to get the whole gear model and input the model to the UG software. Finally, the 3D geometry entity model of gear was got.2. From the view of bionics principle, nine kinds of bionic non-smooth concave surfaces with different sizes and distance of non-smooth units were designed. For small geometry unit and complex form of non-smooth units, the traditional machinery manufacturing methods cannot satisfy to the requirement, and the laser texturing method was adopted to manufacture the non-smooth surfaces. All samples were processed and completed in the JHM-1GY-100B laser NC manufacturing machine. 3. The experimental investigations of anti-wear ability for smooth and bionics non-smooth gear model samples were completed. The micro-tribology tester was adopted to study the micro-tribology characteristics of non-smooth samples. Considering the experimental optimum design theory and orthogonal design, the main four factors and levels effecting the friction and abrasion were confirmed, namely, size(300μm, 250μm, 200μm), distance(550μm, 450μm, 350μm), velocity(140 rpm,110 rpm,80 rpm), load(13 N,10 N,7 N). In this experiment, the wear time of every sample was 90 minutes, and the anti-wear ability of the samples was assessed by the rate of volume abrasion and the friction coefficient. The rate of volume abrasion was measured by the wear width from the XTJ-30 microscope system, and calculated by ΔV= a and K= . Where, a is back and forth sliding distance, d is the wear width, r is the radius of GCr15 steel ball, L is the experimental load, and T is the wear time. The friction coefficient was confirmed by the ratio of the friction force and experimental load. It was found in the contrast wear experiments of smooth and bionics non-smooth gear model samples that the rate of volume abrasion of the smooth sample was bigger, and the increasing vale of volume abrasion rate is between 7.222% and 135.839%. The anti-wear mechanism of bionics non-smooth surface was due to the re-melting strengthening of laser and bionics non-smooth surface morphology. At the same time, the anti-wear ability of several non-smooth concave surfaces with different size and distance of non-smooth unit was compare...
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