Study On Preparation Of Electroplated Grinding Wheel With Abrasive Ordered Arrangement

Due to the disordered arrangement of abrasive in the working layer of traditional grinding wheel,there are redundant abrasive,which will cause the uneven distribution of the abrasive and interfere with each other,which will affect the sharpness of the grinding wheel and the ability to carry coolant,which will easily cause the grinding force and temperature to rise high.The abrasive of the grinding wheel arranged in order is orderly arranged on the grinding layer or working surface,to effectively avoid redundant abrasive and improve the chip holding capacity of grinding wheel.It has good sharpness in grinding.Compared with the traditional grinding wheel,the grinding force is small and the temperature is low.At present,the abrasive wheel with orderly arrangement has been widely used in high efficiency grinding,which is a new type of high efficiency grinding wheel.Electroplating superabrasive wheel with ordered arrangement of abrasive is manufactured by electroplating method.It has the advantages of simple preparation process,suitable for manufacturing grinding wheel with complex surface,strong abrasive holding force of metal coating and good accuracy retention.It is usually used in high-efficiency grinding and machining of difficult to machine materials.A lot of research has been carried out,but there are still some deficiencies in the abrasive layout,manufacturing methods,grinding performance and so on,which need further research.In this thesis,the key technologies such as abrasive arrangement and manufacturing method,electroplating process optimization,grinding performance and so on are studied.A new abrasive arrangement method based on imprint method is proposed,which realizes the rapid dispensing and sanding on the working surface of grinding wheel,and significantly improves the manufacturing efficiency.The mechanism of imprinting,electroplating process,coating performance,grinding performance of grinding wheel and other key aspects are systematically studied,which has a certain significance to promote the development of manufacturing and application technology of electroplating abrasive orderly arrangement grinding wheel.The specific research work is as follows:1.Study on orderly abrasive arrangement and manufacturing method.(1)Orderly arrangement of abrasive.Analyze and discuss the most commonly used phyllodes,matrix,and misalignment arrangements to establish an arrangement model.Matlab software is used to study the influence of the arrangement parameters of the above arrangement on the trajectory of the abrasive for theoretical research.The arrangement of abrasive and the trajectory of movement are analyzed.The results show that the phyllodes arrangement is optimal but the arrangement is more complicated,and the matrix arrangement and the dislocation arrangement are at the same rotation speed,and the dislocation arrangement takes the lead to form an effective envelope surface.Therefore,the imprint dispensing method is suitable for the dislocation abrasive arrangement method,and the arrangement parameters of the typical grain size grinding wheel are optimized.(2)Study on the manufacturing method of abrasive orderly arrangement based on imprint dispensing method.The method and principle of imprint dispensing are studied.The main technical parameters are determined by theoretical analysis and experiment.Design and manufacture the imprint dispensing sanding device.The device includes a dispensing mold,an imprint template,and a rotary indexing device for the grinding wheel.The effects of imprinting template materials,laser hole-making processing methods and the glue viscosity on the performance of the template are studied.The results show that with 80/100 mesh abrasive as the research object,the thickness of the rubber plate is controlled at 1.5mm,and the pore diameter is 0.2±0.01mm.The developed grinding wheel rotary indexing dispensing and sanding device,the maximum dispensing wheel diameter is 400mm,and the rotation speed during dispensing is adjustable at 1°-5°/s.Through the dispensing and sanding test,the effect is better.2.Study on the optimization of electroplating process for orderly arranged grinding wheel.A combination of theoretical analysis and experimental testing was used to study the influence of key factors such as bath composition,current density,power waveform and other key factors on the orderly arrangement of the abrasive,and reveal the influence mechanism of the composite structure of the coating on the holding strength of the abrasive.(1)Component optimization orthogonal test.The effects of bath components such as nickel sulfate,cobalt sulfate and sodium chloride on the tensile strength and hardness of the coating were studied by orthogonal test.The results show that the order of influence on the tensile strength of the coating is nickel sulfate>sodium chloride>cobalt sulfate;The order of influence on the hardness of the coating is:cobalt sulfate>nickel sulfate>sodium chloride.The optimal composition of the optimized plating solution:nickel sulfate is 270 g/L,cobalt sulfate is 30 g/L,sodium chloride is 10 g/L.The tensile strength of the prepared coating was 651Mpa,and the hardness was 39HRC.(2)Effect of pulse current on properties of coatingThe effects of different power supply and different current parameters on the performance of the coating were analyzed by measuring the microhardness and residual stress of the coating.The results show that with the increase of pulse frequency(average current density),the hardness and residual stress curves of the coating first increase and then decrease;When the pulse frequency is 1500Hz,the average current density is 1A/dm~2,the current waveform is rectangular wave,and the duty cycle is 50%,the performance of the coating is the best.At this time,the hardness of the coating is 540 HV and the residual stress is 80 MPa.(3)Analysis of the influence of coating bonding interface microstructure on abrasive holding strength.Adopt super depth of field microscope and SEM approach for abrasive/plating/conductive adhesive between micro combined with the feature of interface were analyzed,and the results show that using the anchor point glue for grinding grain,consolidation point between rubber thickness uniformity of abrasive such as sex influence is significant.Taking 16/18#grinding(abrasive size of about 1 mm)as an example,the maximum difference of contour is 20?m.But the error is less than 2%of the abrasive grain size,which can meet the requirements of electroplating grinding wheel with orderly arrangement of abrasives.3.Experimental study on grinding performance of CBN abrasive wheel with orderly arrangement.The CBN grinding wheel with ordered arrangement of abrasive was prepared by the imprinting dispensing method proposed in this thesis and the electroplating process was optimized.The grinding performance of the CBN grinding wheel with ordered arrangement of abrasive was studied by comparing the grinding performance of the ordered and disordered grinding wheels.The results show that the grinding forces of the ordered and disordered grinding wheels are positively correlated with the grinding depth,and negatively correlated with the linear velocity,but the grinding force of the ordered wheel is lower than that of the disordered wheel;The grinding temperature is positively correlated with the cutting depth and the linear velocity,but the grinding temperature of the ordered wheel is also lower than that of the disordered wheel.It further shows that when CBN abrasive distribution is reasonable and uniform,the redundancy of abrasive is effectively avoided,the grinding wheel has large chip space,the blockage of grinding wheel is avoided,and the grinding force and grinding temperature are effectively reduced.