Main Ways to Improve Cutting Tools for Machine Wheel Tread Profile

This chapter considers the methods to increase the performance and reliability of the reprofile machining of the wheel tread profile. Proceeding from the fact that both in milling and turning, the cutting tool is a key element to ensure performance and reliability of the manufacturing process, the study considers the methods to increase the performance properties of cutting tools. In particular, the study includes the investigation of the following ways to improve cutting tools (carbide inserts) to machine wheel tread profile: replacement of traditional grades of WC-TiC-Co carbides with more efficient ones based on WC-TiC-TaC-Co; application of special thermally conductive pads, gaskets, and pastes to improve the distribution of heat flows in the cutting zone; and application of modern nanoscale composite multilayer coatings (NMCC). It is noted that even higher performance can be obtained by combining the above three methods, in particular, by combining application of special thermal pads and NMCC

Influence of aluminium and molybdenum on properties of coatings and cutting properties of coated tools

The paper presents the results of the investigation focused on the properties of the Cr,Mo-(Cr,Mo)N-(Cr,Mo,Al)N multilayered composite wear-resistant coating with a nanostructured wear-resistant layer. The nanostructure of the coating was investigated using transmission electron microscopy (TEM), the microhardness was measured, and the chemical composition was found. The cutting properties of a tool with the Cr,Mo-(Cr,Mo)N-(Cr,Mo,Al)N coating were studied during the turning of 09G2S silicon-manganese steel. It has been found that the use of a cutting tool with the Cr,Mo-(Cr,Mo)N-(Cr,Mo,Al)N coating reduces the flank wear rate by 1.65 times compared to an uncoated tool

Influence of aluminium and molybdenum on properties of coatings and cutting properties of coated tools

The paper presents the results of the investigation focused on the properties of the Cr,Mo-(Cr,Mo)N-(Cr,Mo,Al)N multilayered composite wear-resistant coating with a nanostructured wear-resistant layer. The nanostructure of the coating was investigated using transmission electron microscopy (TEM), the microhardness was measured, and the chemical composition was found. The cutting properties of a tool with the Cr,Mo-(Cr,Mo)N-(Cr,Mo,Al)N coating were studied during the turning of 09G2S silicon-manganese steel. It has been found that the use of a cutting tool with the Cr,Mo-(Cr,Mo)N-(Cr,Mo,Al)N coating reduces the flank wear rate by 1.65 times compared to an uncoated tool

Influence of the nanolayer structure of coatings on the cutting properties of tools

The paper is focused on the influence of the thickness of nanolayers in the Ti-TiN-(Ti,Cr,Al)N coating on the cutting properties of the tools during the turning of 09G2S silicon-manganese steel. Coatings with the nanolayer thicknesses of 302, 70, and 16 nm were considered. The conducted studies have revealed that a tool with a coating in which the nanolayer thickness is equal to 16 nm demonstrates the longest tool life. At the same time, for such tool, the wear pattern is more balanced, and signs of brittle fracture on the coating are less pronounced. The Ti-TiN- (Ti,Cr,Al)N coating with the nanolayer thickness of 16 nm provides an increase in the tool life by 3.5 times compared to an uncoated tool and by 1.3–1.5 times compared to the tools with the Ti-TiN-(Ti,Cr,Al)N coating with thicker nanolayers

Influence of the nanolayer structure of coatings on the cutting properties of tools

The paper is focused on the influence of the thickness of nanolayers in the Ti-TiN-(Ti,Cr,Al)N coating on the cutting properties of the tools during the turning of 09G2S silicon-manganese steel. Coatings with the nanolayer thicknesses of 302, 70, and 16 nm were considered. The conducted studies have revealed that a tool with a coating in which the nanolayer thickness is equal to 16 nm demonstrates the longest tool life. At the same time, for such tool, the wear pattern is more balanced, and signs of brittle fracture on the coating are less pronounced. The Ti-TiN- (Ti,Cr,Al)N coating with the nanolayer thickness of 16 nm provides an increase in the tool life by 3.5 times compared to an uncoated tool and by 1.3–1.5 times compared to the tools with the Ti-TiN-(Ti,Cr,Al)N coating with thicker nanolayers

Diagnostic Techniques for Electrical Discharge Plasma Used in PVD Coating Processes

This article discusses the possibilities of two methods for monitoring Physical Vapor Deposition (PVD) process parameters: multi-grid probe, which makes it possible, in particular, to determine the energy distribution of ions of one- or two-component plasma and spectrum analyzer of the glow discharge plasma electromagnetic radiation signal based on the Prony–Fourier multichannel inductive spectral analysis sensor. The energy distribution curves of argon ions in the low-voltage operation mode of ion sources with closed electron current have been analyzed. With a decline in the discharge current, the average ion energy decreases, and the source efficiency (the ratio of the average ion energy W to the discharge voltage U) remains approximately at the same level of W/U ≈ 0.68, …, 0.71 in the operating voltage range of the source. The spectrum analyzer system can obtain not only the spectra at the output of the sensor, but also the deconvolution of the spectrum of the electromagnetic radiation signal of the glow discharge plasma. The scheme of a spectrum analyzer is considered, which can be used both for monitoring and for controlling the processing process, including in automated PVD installations

Influence of Thickness of Multilayer Composite Nano-structured Coatings on Tool Life of Metal-Cutting Tool

The paper is focused on turning of structural steels C45. Cutting tools were represented by carbide cutting inserts without coatings, with reference coating TiAlN, as well as with multilayered composite nano-structured coatings Ti-TiN-(TiCrAl)N and Zr-ZrN-(ZrCrNbAl)N (of different thickness of 3-7 μm). The following studies of the properties of coated tools were carried out: measurement of microhardness and strength of adhesion bonds in the “tool-coating” system and investigation of elemental and phase compositions of coatings. The cutting tests were carried out at the following cutting modes: f = 0.2 mm/rev; аp = 1.0 mm; vc = 200, 250, 300, 350 and 400 m/min

Influence of Thickness of Multilayered Nano-Structured Coatings Ti-TiN-(TiCrAl)N and Zr-ZrN-(ZrCrNbAl)N on Tool Life of Metal Cutting Tools at Various Cutting Speeds

This paper considers the influence of thickness of multilayered nano-structured coatings Ti-TiN-(TiCrAl)N and Zr-ZrN-(ZrCrNbAl)N on tool life of metal cutting tools at various cutting speeds (vc = 250, 300, 350 and 400 m·min−1). The paper investigates the basic mechanical parameters of coatings and the mechanism of coating failure in scratch testing depending on thickness of coating. Cutting tests were conducted in longitudinal turning of steel C45 with tools with the coatings under study of various thicknesses (3, 5, and 7 µm), with an uncoated tool and with a tool with a “reference” coating of TiAlN. The relationship of “cutting speed vc—tool life T” was built and investigated; and the mechanisms were found to determine the selection of the optimum coating thickness at various cutting speeds. Advantages of cutting tools with these coatings are especially obvious at high cutting speeds (in particular, vc = 400 m·min−1). If at lower cutting speeds, the longest tool life is shown by tools with thicker coatings (of about 7 μm), then with an increase in cutting speed (especially at vc = 400 m·min−1) the longest tool life is shown by tools with thinner coating (of about 3 μm)

Influence of the Ti-TiN-(Y,Ti,Al)N Nanolayer Coating Deposition Process Parameters on Cutting Tool Oxidative Wear during Steel Turning

Ti-TiN-(Y,Ti,Al)N coatings with a three-layer architecture (adhesive Ti layer, transition TiN layer, and wear-resistant (Y,Ti,Al)N layer) were studied. When depositing coatings, three arc current values of the yttrium cathode were used: 65, 85, and 105 A. The yttrium contents in the coatings were 30, 47, and 63 at. %, respectively. When turning 1045 steel, a coating with 30 at. % yttrium showed better wear resistance compared to a commercial (Ti,Cr,Al)N coating. The coating with 63 at. % yttrium did not show an increase in wear resistance compared to the uncoated sample. Nanolayers with a high yttrium content are oxidized more actively compared to nanolayers with a high titanium content. Phase analysis shows partial retention of the initial phases (Y,Ti,Al)N and (Ti,Y,Al)N during the formation of the Y2O3 oxide phase in the outer layers of the coating and the presence of only the initial phases in the deep layers. Coating nanolayers with high contents of aluminum and yttrium lose their original structure to a greater extent during oxidation compared to layers without aluminum

Investigation of the Properties of Multilayer Nanostructured Coating Based on the (Ti,Y,Al)N System with High Content of Yttrium

The studies are focused on the properties of the multilayer composite coating based on the (Ti,Y,Al)N system with high content of yttrium (about 40 at.%) of yttrium (Y). The hardness and elastic modulus were defined, and the resistance to fracture was studied during the scratch testing. Two cubic solid solutions (fcc phases), including c-(Ti,Y,Al)N and c-(Y,Ti,Al)N, are formed in the coating. The investigation of the wear resistance of the (Ti,Y,Al)N-coated tools during the turning of steel in comparison with the wear resistance of the tools with the based on the (Ti,Cr,Al)N system coating and the uncoated tools found a noticeable increase (by 250%–270%) in rake wear resistance. Active oxidation processes are observed in the (Ti,Y,Al)N coating during wear. It can be assumed that yttrium oxide is predominantly formed with a possible insignificant formation of titanium and aluminum oxides. At the same time, complete oxidation of c-(Y,Ti,Al)N nanolayers is not observed. Some hypotheses explaining the rather high performance of a coating with a high yttrium content are considered