Research On Laser Bionic Structuring And Grinding Performance Of Bronze-Bonded Diamond Grinding Wheels

In order to solve the problem of thermal damage to the workpiece and blockage of the grinding wheel during grinding of alumina ceramics,this paper used the organism with strong hydrophilic and high anti-wear surface as the bionic prototype for the first time,and explored the laser preparation process and grinding of bionic structured grinding wheel.performance.In this paper,the surface of the regular hexagonal groove structure such as tree frog toe,aquatic beetle and oriental sand boa is used as bionic prototypes to carry out research on laser bionic structured grinding wheel and grinding performance.The influence of laser parameters on structure size accuracy,the relationship between structure size and grinding wheel surface contact angle,and the grinding performance of bionic structured grinding wheel are studied.The details are as follows:1)An experimental platform for laser-fabricated bionic structured grinding wheel was built,and the influence of laser parameters on the size and morphology of ablated structures was revealed through process experiments and theoretical analysis.The variation law of the side length,spacing and depth of the structure with the overlap rate of laser points,line overlap rate,power and scanning times was explored,and the laser parameters were optimized;Due to the Gaussian distribution of the energy of the laser beam,the structure boss appears layered,and the depth increase is limited;Aiming at this defect,a new preparation method is proposed in this paper,which is the coordinated control method of laser focus position and scanning times.The laser focal plane is always located in the ablation plane of the grinding wheel to improve the depth dimension and shape accuracy of the structure.2)Based on the three-phase contact line theory of droplets on the surface of the structure,combined with the technological experiments,the influence of the structure size on the contact angle and hydrophilicity of the grinding wheel surface was clarified.The relationship between the side length,depth and spacing of the structure on the contact angle of the grinding wheel surface was explored,and it was found that the contact angle decreased with the increase of the depth and spacing,while the effect of the side length was small.Compared with the conventional grinding wheel,the surface of the structured grinding wheel drives the spreading of the droplet due to the increased solid-liquid contact area,the movement of the three-phase contact line of the droplet and the increase of the Laplace pressure inside the droplet.The hydrophilicity of the grinding wheel surface is enhanced.3)The grinding performance of bionic structured grinding wheels was comprehensively evaluated by grinding alumina ceramics.Compared with the conventional grinding wheel,the bionic structured grinding wheel enhances the lyophilic ability of the grinding fluid,reduces the grinding temperature and the thermal damage of the workpiece surface,and obtains a better workpiece surface quality.The structure of the surface of the grinding wheel after grinding has no chipping or breaking,and has good wear resistance.In addition,the bionic structured grinding wheel can bring more grinding fluid into the grinding area,wash away a large amount of grinding chips,and the groove area has a chip storage function.This bionic structured grinding wheel improves the defects of surface blockage caused by thermal damage on the workpiece surface caused by high temperature of alumina ceramic grinding and difficulty in chip removal,and reflects better grinding performance.