酚醛树脂含水率对金刚石砂轮磨削硬质合金的影响

The Influence of the Rate of Water Content in Phenolic Resin on Grinding Cemented Carbide with Diamond grinding wheel

采用不同含水率的酚醛树脂金刚石砂轮,对硬质合金YG8进行了平面磨削试验,研究了含水率变化导致的砂轮磨削性能变化对磨削比、磨削功率和工件表面粗糙度的影响规律,并对砂轮磨削后表面形貌进行了观测,揭示了酚醛树脂金刚石砂轮磨削性能随含水率变化的规律。试验结果表明:含水率越高,砂轮的组织均匀性就越差,机械性能和磨削性能不稳定且总体趋势变差。磨削比、Ra值在一个耐用度周期内波动较大,不适合精密磨削加工。为了获得良好且稳定的粗糙度表面,应选用含水率小于0.3%的树脂原材料制作砂轮。含水率较低时(<0.3%)磨削功率相对稳定,砂轮表面磨粒脱落率低。但不是含水率越高时磨削性能越差,砂轮的磨削比、磨削钝化速度、粗糙度与含水率不是线性关系。

Using phenolic resin diamond grinding wheel with different rate of water content the surface grinding tests for cemented carbide workpiece （YG8） were carried on. The law for change of grinding wheel grinding performance, such as grinding ratio, grinding power and workpieee surface roughness, caused by rate of water content was studied. Then grinding wheel surface morphology were observed after the grinding, which revealed that the law of phenolic resin bond diamond wheel grinding performance changed with the rate of water content. The results showed that the higher rate of water content was, the worseuniformity of the grinding wheel organization was, and the general trend of mechanical properties and grinding performance was not stable and became worse. Grinding ratio and Ra value fluctuated obviously in a durability cycles, which was not suitable for precision grinding processing. In order to obtain well and stable surface roughness, the rate of water content of the resin less than 0.3% should be choose for grinding wheel raw materials. When the rate of water content was less than 0.3% , grinding power was relatively stable, and less abrasive was brushed off. But higher rate of water content isn＇t always worse. The grinding ratio, grinding passivation speed, roughness and the rate of water content was nonlinear relationship.