**6. Conclusion**

Reprofiling of the wheel tread profile is an important and large-scale manufacturing challenge. Both in milling and turning, the cutting tool is a key element ensuring efficiency and reliability of manufacturing process. The improvement of the metal cutting tools can be carried out in several directions at once, as follows:


Even higher performance can be obtained by combining the above three methods, in particular, by combining application of special thermal pads and NMCC.

The analysis of the results of laboratory and industrial tests has shown that the use of the developed tool system, including carbide inserts with NMCCs and set of structures for mounting the insert on the tool holder, including high heatconducting ceramic-polymer pads with high thermal conductivity increased the actual contact bearing surface between the carbide insert and the holder intensifies the effective heat transfer along bearing surface of the insert. The combined effect of the increase in heat transfer and reduction of frictional heat sources due to application of the developed NMCCs showed a significant reduction of the thermal stress of the cutting system during roughing of rolling stock products. This new approach has positively transformed the character of the tool wear, and brought in an improvement of the tool life up to four times by increasing the reliability of the tool due to reduction of the coefficient of tool life variation.

The technology of modifying treatment of carbide tools was developed, which increases wear resistance of tools to high-temperature creep and tool failure because of ductile fracture of its cutting part. That is achieved by introducing between the supporting surfaces of tool holder and cutting carbide inserts a special paste (AlSink-3) on the basis of a mixture of oxides of aluminum and zinc with an silicon organic solvent that improves thermal conductivity of cemented carbide by filling air gaps between the supporting surfaces and by application of nanodispersed multilayered composite coatings, which reduce contact stresses and power of friction heat sources under severe reprofiling machining of hardened running surface of rail wheel pairs. It was found out that wear resistance of tools made of carbide grade (WC-TiC-Co) with thermally conductive interface and nanodispersed multilayered composite coating on the basis of Ti-TiN-TiAlN was up to two times higher than wear resistance of the inserts with standard coatings.
