The development of CBN grinding wheel grinding technology with high quality

The development of CBN grinding wheel grinding technology with high quality 2020 - 06 - 24' Introduction 】 CBN ( Cubic boron nitride, Cubic boron nitride) Is a kind of hardness is second only to diamond abrasive. CBN grinding wheel grinding with high efficiency, high machining accuracy, long service life, and many other advantages, especially the application of ceramic bond CBN grinding wheel is greatly promoted the process of the grinding process, it is also very suitable for grinding of bearing parts. How to realize the high quality of CBN grinding wheel grinding, equipment, tools, materials, conditions of grinding, grinding fluid, processing environment factors can't be ignored. 01 CBN grinding wheel and grinding wheels compared to ordinary grinding wheel grinding capacity ( Cross-sectional area per unit time grinding) General is 1 ~ 3 mm3 / ( mms） 。 The use of alumina or silicon carbide abrasive, hardness is 2100 ~ 2500 HK, will be together and the bond strength of abrasive consolidation is low, because of the grinding force and the sharpness, often crushing and grinding grain loss, grinding wheel surface state change constantly, and often short service life of grinding wheel dressing, low machining efficiency. CBN grinding wheel in the grinding capacity of 1 ~ 15 mm3 / ( mms） , CBN abrasive hardness is 4700 hk, use the high strength bond ( Ceramic bond) Consolidation will CBN grits together, the incidence of abrasive particle breakage or loss is low. Therefore, as the processing, the change of the grinding wheel surface state is very small, grinding precision can keep for a longer time. 02 grinding surface texture, high quality grinding, the key point of the grinding surface texture. Not only to ensure that the surface roughness, straightness, roundness and other grinding accuracy, but also to ensure that when the reflected light from the grinding surface beautiful sex. For CBN grinding wheel, even if the surface roughness and using conventional grinding wheel is the same, flutter in the vertical direction may be prone to grinding stripe ( The marks) , on the grinding direction possible homogeneous squamous pattern. 3 how to achieve the high quality of CBN grinding wheel grinding grinding equipment, tools, materials, surface grinding conditions, grinding fluid, processing environment, and many other factors, ignoring these factors will not be able to obtain high quality of the grinding surface. In order to use the CBN grinding wheel to realize high quality grinding, need to take measures: 1) Establish a surface texture visual measurement/analysis method using optical interference of non-contact 3 d contour instrument analysis of measurement data to add a variety of methods, which can accurately squamous pattern, measurement and analysis. Will change to actual grinding surface quantitatively associated with adverse factors of surface texture, and according to the factors of contribution rate effectively improve surface texture. 2) Bad surface texture analysis of the factors by grinding cross section measurement, based on the equipment specification and grinding conditions such as frequency analysis was carried out on the surface irregularity, determine the cause of the vibration lines and squamous pattern, the results showed that the main associated with grinding wheel switch frequency, influence factors include: the vibration of the grinding wheel spindle rotation system calibration, grinding wheel, grinding condition and the grinding force, etc. 04 CBN grinding wheel grinding technology with high quality development of 1) Perfect trace transverse vibration reduction countermeasures to reduce the feed processing equipment related factors in the process of vibration, measure the shaft, motor and belt pulley their amplitude, after the correction of dynamic balance of these parts for assembly, eventually establish and improve the vibration of the countermeasures, will be near the point of grinding wheel in the front of the level of vibration control in setting. 2) High precision finishing technology in the process of modification of CBN grinding wheel cutting edge, using a rotary diamond sharp cutting edge grinding wheel dresser, and by adjusting the blade size to make it even, to optimize the modification status. 3) When grinding rotary workpiece surface texture of the optimization algorithm in minimize the relative vibration of grinding wheel and workpiece, but cannot eliminate completely. For the disturbance caused by forced vibration and self-excited vibration caused by cutting performance change, using the algorithm can reduce the nonuniformity of the grinding surface. 4) The development of the low grinding force grinding wheel in order to ensure that under the small feeding to make the final grinding homogenization, CBN grinding wheel in the development of the grinding force decrease. In order to guarantee the cutting performance of the grinding wheel, will focus on grain type, grinding grain shape, reduce the binder content, and improve adhesive. The author: Day] H。 盛田昭夫《捷工程期刊》( Source: the journal bearing)