Development of cBN(cubic boron nitride)-Coated Cutting Tools

在本研究中，我们制造并评估了cbn涂层刀具，该刀具可能适用于难切削材料的切削工艺和环保制造工艺。众所周知，cBN具有优良的耐热性和抗磨性能，但其抗倾性不足。因此，我们认为cBN涂层刀具，在碳化钨基体上附着一层薄薄的cBN膜，具有与上述性能相当的性能。首先，研究了PVD法制备的cBN薄膜的摩擦学性能。结果表明，cBN膜在大气和真空条件下均具有较低的摩擦系数和抗磨性能，模拟了实际切削过程中的刀具刃口状况。接下来，我们研究了实际刀具的切削性能，如cbn涂层钻头和球头立铣刀。我们制作了这些刀具，并通过若干切削试验，例如模具钢工件的切削试验，评估了cbn涂层刀具的优点。结果表明，cbn涂层刀具比高速钢和碳化钨涂层刀具具有更好的切削性能。然而，我们也观察到，由于cBN膜的厚度和附着力不足，制备的cBN涂层刀具的切削性能明显不如传统的tin和tin涂层刀具。最后，采用特殊设计的切削刃对烧结cBN球头立铣刀的切削性能进行了研究。预计这些刀具具有良好的切削性能，与cbn涂层刀具相似，具有大厚度和良好的粘附性能。实验结果表明，与传统的镀钛碳化钨立铣刀相比，新设计的烧结cBN立铣刀具有优异的切削性能。少

In this study, we fabricated and evaluated cBN-coated cutting tools, which may be applicable to the cutting process of difficult-to-cut materials and environmentally friendly manufacturing processes. It is well known that cBN has excellent heat resistance and antiwear properties, but its anti-tipping property is insufficient. Therefore, we consider that a cBN-coated cutting tool, in which a thin cBN film is adhered on a tungsten carbide substrate, has properties comparable to those mentioned above. First, we investiga1ed the tribological properties of the cBN film, which was fabricated by the PVD process. The results showed that the cBN film has excellent tribological properties, such as a low frictional coefficient and an antiwear property, under both atmospheric and vacuum conditions, which simulated the tool edge condition in an actual cutting operation. Next, we investigated the cutting properties of actual cutting tools, such as cBN-coated drills and ball-nosed end mills. Namely, … More we fabricated these tools and evaluated the advantageous characteristics of the cBN-coated tools through several cutting tests, such as the cutting of a mold steel workpiece. The results clarified that the fabricated cBN-coated tools have better cutting performance than conventional tools made of high-speed steel and tungsten carbide. However, we also observed that the cutting performance of the fabricated cBN-coated tools is significantly less progressive than those of conventional TiN-and TiAIN-coated tools, because the thickness and adhesion of the cBN film are insufficient. Finally, we investigated the cutting performance of the sintered cBN ball-nosed end mills with a specially designed cutting edge. It was expected that these tools have good cutting performance, similar to that of the cBN-coated tool with large-thickness and good adhesion properties. The results of our experiment clarified that the newly designed sintered cBN end mills have excellent cutting performance, compared with a conventional TiAIN-coated tungsten carbide end mill. Less