Hexagonal boron nitride (h-BN) is an excellent solid lubricant that can be used to improve the processability of difficult-to-cut materials. We tried to solve the processing difficulty of vermicular graphite cast iron (VGI) by adding 0.0144 wt% of h-BN micro-powders into VGI (tensile strength R_m ≥ 450 MPa). Then, we use coated cemented carbide tools (CCC tools, coatings TiC + Al₂O₃) to carry out the turning test on VGI. By analyzing the maximum wear maxVB of the flank face, the wear morphology characteristics of rake face, and the residue on rake face, the wear mechanisms of the tool are studied. Finally, the role of h-BN in the processing process is assumed and the Gray-Markov model of maxVB is modeled. It can be found that: when v = 100~200 m/min, the tool life of cutting VGI with h-BN (sample A) was twice that of cutting VGI without h-BN (sample B). In particular, when v = 200 m/min, the tool life of cutting sample A is as high as 8 min. It is shown that h-BN can make CCC tools have the same advantages as PCBN tools in cutting VGI. In cutting sample A, the wear mechanisms of rake face are abrasive wear, adhesive wear, and oxidation wear, and adhesive wear is the main cause of tool failure. Given the cutting speed, when t ≥ 2 min, the adhesive wear of the rake face in cutting sample A is slighter than that in cutting sample B. h-BN can effectively reduce the adhesive wear. The error of maxVB predicted by Gray-Markov model is Δ ≤ 1.25%, which can be used to analyze and predict the tool wear of VGI with h-BN.

六方氮化硼（h-BN）是一种出色的固体润滑剂，可用于提高难切削材料的加工性能。我们试图通过添加的h-BN的微粉末的0.0144重量％到VGI（拉伸强度来解决蠕墨铸铁（VGI）的处理难度ř_米≥450兆帕）。然后，我们使用涂层硬质合金工具（CCC工具，涂层TiC + Al ₂ O ₃）对VGI进行车削测试。通过分析后刀面的最大磨损最大值VB，前刀面的磨损形态特征以及前刀面的残留物，研究了刀具的磨损机理。最后，假设了h-BN在加工过程中的作用，以及最大VB的Gray-Markov模型被建模。可以发现：当v = 100〜200 m / min时，用h-BN切削VGI（样品A）的刀具寿命是不使用h-BN切削VGI（样品B）的刀具寿命的两倍。特别是，当v = 200 m / min时，切削样品A的刀具寿命高达8分钟。结果表明，h-BN可以使CCC工具在切割VGI方面具有与PCBN工具相同的优势。在切削样品A时，前刀面的磨损机理是磨料磨损，粘着剂磨损和氧化磨损，而粘着剂磨损是工具失效的主要原因。鉴于切割速度，当吨≥2分钟，在切割样品A的前倾面的粘着磨损是在切割样品B的h-BN可以有效地减少粘附磨损较轻比。最大VB的误差 Gray-Markov模型预测的Δ≤1.25％，可用于分析和预测带h-BN的VGI的刀具磨损。