基于固体润滑剂与原位反应双机制自润滑陶瓷刀具

采用真空热压烧结工艺，以Al2O3/TiB2为基体、CaF2为添加剂制备了Al2O3/TiB2/CaF2(ABF)自润滑陶瓷刀具，并对其进行了摩擦磨损试验和淬硬钢干切削试验。在摩擦磨损试验过程中，测定了4种不同CaF2含量的ABF陶瓷材料样品。摩擦磨损试验结果表明，ABF材料的平均摩擦因数随着CaF2含量的增加而减小，这是因为固体润滑剂CaF2在磨损过程中生成的润滑膜起到了一定的减摩作用。将ABF刀具和普通陶瓷刀具(AG2)在120 m/min切削速度下对45淬硬钢进行干切削试验，切削试验结果表明，ABF前刀面的平均摩擦因数比AG2陶瓷刀具前刀面的平均摩擦因数要显著偏小，主要原因是ABF自润滑陶瓷刀具在高速切削时，固体润滑剂CaF2和自身TiB2的原位反应同时生成了润滑膜，这种双重机制下生成的润滑膜具有极佳的润滑性能，其润滑效果随温度和切削速度的增加而显著提高。

Selflubricating Ceramic Cutting Tool with Solid Lubricantbased and a Doublesitu Reaction Mechanism

A selflubricating ceramic cutting tool was produced by the hot pressing vacuum sintering process, with the substrate of Al2O3/TiB2 and the addition of CaF2. Meanwhile the dry cutting tests were carried out. In the process of friction and wear test, there were four Al2O3/TiB2/CaF2(ABF) materials with different contents of CaF2. The results show that the friction coefficient of the material decreases with the increase of its contents of CaF2.The formation of CaF2 in the wear layer of a solid lubricating film during the antifriction lubricant film played a role, in the cutting tests which were carried out with respect to 45 steel at the speed of 120 m/min, the average friction coefficient of the ABF tools is much lower than that of the normal ceramic knives tool (AG2). And the main reason was the lubricating film which generated by the solid lubricant CaF2 and the situ reaction of TiB2,when the ABF selflubricating ceramic tool was cutting under the high speed. Meanwhile, with the increase of temperature and the cutting speed, its lubricating effect is improved significantly.