| At present,hard and brittle materials are applied in many fields with their unique properties,such as aerospace,ship,information and military industry.Due to the characteristics of high strength,high hardness and brittleness of the material,the grinding process of super-hard diamond grinding wheel with high rotation speed has become the most important processing method.In order to ensure the surface quality of the material,higher requirements are put forward for the shape precision and grinding performance of the grinding wheel.Electroplated diamond grinding wheel is widely used in the precision machining of hard and brittle materials because of its high exposure and bonding strength.In the process of grinding wheel preparation,although the matrix can maintain a high precision,in the mixing and molding process,due to the random distribution of diamond grinding grains,may cause the phenomenon of grinding grain accumulation,resulting in uneven grinding grain contour on the surface of the grinding wheel,affecting the processing surface quality.With the rapid development of grinding wheel dressing technology,the precision and durability of grinding wheel are obviously improved.which solves the difficult problem of grinding wheel dressing for super hard abrasive.All kinds of finishing technology itself has some limitations,however,affect the wide use of grinding wheel,therefore,in this paper,on the basis of the diamond pen ordinary dressing additional ultrasonic vibration,put forward the method of ultrasonic vibration dressing diamond grinding wheel,the method can realize abrasive grinding wheel surface such as sex,to form new grinding blade,greatly improve the shape of grinding wheel grinding performance,precision and improve the machining efficiency,greatly improved the surface quality of the materialFirstly,based on the theory of wave propagation in the variable-section bar,the structure size of the variable-section bar was designed by combining theory and simulation analysis,the size of the diamond pen trimming tool head was determined by the boundary conditions,and the amplitude of the whole ultrasonic working system was tested and verified,which ensured the stability of the working systemThe mechanism of ultrasonic vibration dressing is analyzed,and the characteristics of ultrasonic vibration dressing are discussed.The results show that in the dressing ultrasonic vibration,there are two kinds of effects in the dressing process of grindir namely impact and shear.When the diamond pen is just in contact with the abrasive the impact caused by ultrasonic vibration plays a major role,and the abrasive par micro-broken to form a new grinding edge.When the diamond pen is separated abrasive particle,the diamond pen and the abrasive particle form a shear surface d rotation of the grinding wheel,and the interaction between the abrasive particle diamond pen is mainly shear.According to test results,analysis of amplitude,lead three dressing grinding wh and repair process parameters on the influence law of coarse and fine grained grindi surface topography,for shaping the grinding wheel surface topography,scanning microscope after concluded that appropriate increase amplitude is helpful to enh grinding performance of wheel,but high amplitude will be bonded on the surface of a wheel grinding grain and damage effect;Too high speed of grinding wheel makes the particles break off due to shear action and weakens the dressing effect.Small dres makes grinding grains on the surface of the grinding wheel be completely dre grinding grains keep the same contour,and the surface morphology of the grinding good.Finally,the grinding performance of the grinding wheel is tested by grinding grinding surface morphology of the grinding wheel after dressing is better than th dressing.Moreover,the surface roughness of the workpiece decreases from 2.29?m to The grinding force is significantly reduced,and the surface grinding performanc grinding wheel is greatly improved after dressing. |
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