磨削液对砂轮磨削轴承钢流体动压效应的影响

Influence of Grinding Fluid on Dynamic Pressure Effect of Grinding Wheel Grinding Bearing Steel

为了研究不同的磨削液对陶瓷刚玉砂轮外圆磨削轴承钢(GCr15)时的流体动压效应的影响,基于弹性流体动力润滑理论,建立稳态微观热弹流砂轮模型,对比分析水溶性磨削液、乳化液、油溶性磨削液、石蜡油磨削液对流体动压效应的影响,以及采用不同磨削液时磨削区的温度变化,并分析磨削液为乳化液时油相体积分数的不同对磨削区流体动压效应的影响。结果表明:无论是否考虑粗糙度的影响,采用石蜡油磨削液的整体压力最小,整体膜厚最大,而采用水溶性磨削液的磨削区温度要低于油溶性磨削液;综合考虑各种因素,选用乳化液作为磨削液,可获得较好的磨削效果和较低的表面磨削温度;乳化液的油相体积分数越大,整体压力越小,最小膜厚越大,但磨削区的温度上涨也越迅速;为保证磨削区温度不至太高,油相体积分数一般不超过20%。

A steady-state micro-thermal elastohydrodynamic lubrication grinding wheel model was established to study the effects of different grinding fluids on the hydrodynamic effects of ceramic corundum grinding wheels on cylindrically ground bearing steels(GCr15),based on the theory of elastic hydrodynamic lubrication.The effects of water-soluble grinding fluid,emulsified liquid,oil-soluble grinding fluid and paraffin oil grinding fluid on hydrodynamic pressure,and the temperature changes of the grinding zone with four different grinding fluids were compared and analyzed.The effect of different oil phase volume fraction on the dynamic pressure effect of the grinding zone was analyzed when the grinding fluid is an emulsified liquid.The results show that regardless of the effect of roughness,the overall pressure is the lowest and the overall film thickness is the largest when paraffin oil is used as grinding fluid,while the grinding zone temperature with water-soluble grinding fluid is lower than that with oil-soluble grinding fluid during the grinding process.Considering various factors comprehensively,emulsions are selected as the emulsified liquid to obtain better grinding effect and lower surface grinding temperature.The larger the oil phase volume fraction of the emulsified liquid,the smaller the overall pressure,the larger the minimum film thickness,and the faster the temperature rise in the grinding zone.To ensure that the temperature in the grinding area is not too high,the oil phase volume fraction is generally not more than 20%.