Study On Preparation And Properties Of Vitrified Stacked Abrasive Using Pressure Spray Drying Method

Traditional diamond polishing liquid possesses problems such as poor self-sharpness,low polishing efficiency and poor surface consistency of workpieces when polishing hard and brittle materials such as ceramics,glass,stone,hard alloys etc.which limits it’s applications.Improvement of the self-sharpness of diamond abrasive,efficiency and the polishing performance of diamond polishing liquid become crucial in this field.In this paper,diamond powder works as the abrasive grain and the solid bond and mixed sol bond as the binder.The spherical vitrified bond diamond abrasive was prepared by pressure spray drying method.The related technology and theory were discussed problem.Results are as following:1)Using low-melting solid vitrified bond as the binder and 2000# diamond powder as the abrasive grain.The spherical diamond abrasive was prepared by pressure spray drying method.The degree of matching between the properties of the binder and the Diamond abrasive was systematically studied,the spray drying parameters were optimized to investigate and the effect of the combined dose on the particle size distribution,microstructure,polishing performance and surface roughness of the deposited abrasive.The results show that: The spray drying parameters were optimized and determined: spray pressure is 0.4 MPa,drying temperature is 200°C,orifice diameteris 0.4~0.5 mm,mass ratio of initial material to water is 2.5:1~3:1.The sphericity of the prepared diamond stacking abrasive is better and the particle size is concentrated at 160/200~200/250 mesh.When the bonding dose is 20wt% after sintering at 620°C/1h,the bonding agent can achieve better coating of the diamond abrasive forming a uniform holding force and at the same time the diamond stacked abrasive polishing liquid has the lowest surface roughness after polishing the marble tile.The lowest roughness is Ra0.914 μm.2)Using mixed sol solution as the binder and 3000# diamond powder as the abrasive grain to prepare a spherical diamond stacking abrasive by pressure spray drying method.The results show that: When the peptizing temperature is 70°C,the ratio of acid to aluminum is 0.07 and the initial solid content is 35wt%,the prepared aluminum sol has good stability and suitable viscosity.When pH value of the mixed sol is 1.5 and the preparation temperature is 60 °C,the stability of the mixed sol is the best,and the average particle size of the mixed sol solution is 452.8nm,which canmeet the requirements of the preparation of 3~5 um diamond piled abrasive.When the combined dose is 20wt%,the polishing efficiency of the diamond stacked abrasive prepared by the mixed sol binder method is 0.88g/min for the marble tile,41.94%higher than that of the diamond powder and the surface roughness is reduced by19.54%.It is Ra0.873 μm.