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In this study the microstructure and wear characteristics of Multilayer AlCrN coated AISI 410 stainless steel with the physical vapor deposition technique.

The friction and wear performance of the ML-AlCrN-coated AISI410 steel and uncoated AISI410 steel sliding against with high carbon steel were investigated by the ball cratering test at room temperature. The tribological characteristic of coated AISI410 steel was determined by applying constant sliding velocity of 0.3927 ms⁻¹ and total sliding distance of 353.43 m over various normal loads of 2, 3 and 4 N.

The AlCrN-coated AISI410 steel showed excellent wear performance up to 4 N load. The uncoated AISI410 steel showed good to acceptable wear resistance up to 2 N load. The wear tracks and worn surface were examined by scanning electron microscopy with energy-dispersive X-ray spectroscopy (EDS) attachment for explaining the differences in wear mechanism.

The ability of coating to delay substrate oxidation, with an excellent wear resistance, was identified under different parameters on worn areas.

Deep drilling of hardened steels is a difficult machining operation because of the high wear level of tools. This paper aims to present the main wear mechanisms observed in physical vapor deposition (PVD)-coated twist drills during deep drilling of SAE4144M steel under minimum quantity lubrication, assessed in the production of injection holders.

Two PVD coatings were tested: TiAlN and AlCrN, industrially processed, the last one being a multilayer coating. The workpiece was heat treated for a hardness of 39 HRC to be applied in a diesel engine component. The tests were performed in an industrial environment for a fixed number of holes. Two levels of cutting speed and feed rate were selected for the experiments. In addition, minimum quantity of lubrication (MQL) was compared with conventional lubrication. Scanning electron microscope was used to reveal the wear mechanisms.

Spalling of PVD-coating was revealed for conventional lubrication, while adhesion was observed in MQL conditions. The use of multilayered AlCrN-based coating promoted a significant reduction of adhered material on the twist drill, which is the reason for this selection in industrial operation.

Results showed that the MQL regime can be applied for this industrial application.

A detailed description of wear mechanisms, which allows a suitable selection of coating and machining variables was found for a very difficult operation, using a more economic process in terms of lubrication.

The purpose of this study was to compare machining performance between chemical vapor deposition (CVD)- and physical vapor deposition (PVD)-coated cutting tools to obtain the optimal cutting parameters based on different types of tools for machining titanium alloy (Ti-6Al-4V).

The design of the experiment was constructed using the response surface methodology (RSM) with the Box–Behnken method. Two types of round-shaped tungsten carbide inserts were used in this experiment, namely, PVD TiAlN/AlCrN insert tool and CVD TiCN/Al₂O₃ insert tool. The titanium alloy (Ti-6Al-4V) material was used throughout this experiment. The tool wear and microstructure analysis were measured using a tool maker microscope, an optical microscope and a scanning electron machine.

The PVD TiAlN/AlCrN insert tool produces the lowest tool wear that significantly prolongs the cutting tool life compared to the CVD TiCN/Al₂O₃ insert tool. In addition, depth of cut was the main factor affecting the tool life, followed by cutting speed and feed rate.

This study was conducted to compare machining performance between CVD- and PVD-coated cutting tools to obtain the optimal cutting parameters based on different types of tools for machining titanium alloy (Ti-6Al-4V). In addition, the information presented in this paper helps reduce the manufacturing cost and setup time for machining titanium alloy. Finally, tool wear comparison between PVD- and CVD-coated titanium alloys was also presented for future improvement for tool manufacturing application.

The purpose of this study is to investigate wear mechanisms of a multi-layered TiAlN/AlCrN-coated carbide tool during the milling of AISI 4340 steel under cryogenic machining.

The wear progression was measured using a toolmaker microscope and an optical microscope. Later, a field emission scanning electron microscope and energy-dispersive X-ray analysis were used to investigate the wear mechanisms in detail.

A comprehensive analysis revealed that the main causes of tool wear mechanisms were abrasion and adhesion wear on the flank face.

The investigations presented in this paper may be used by the machining industry to prolong the tool life at higher cutting speed by the application of liquid nitrogen.

This study aims to investigate the surface modification on 20CrMnTi gear steel individually treated by diamond-like carbon films and nitride coatings.

For this purpose, the mechanical properties of a-C:H, ta-C and AlCrSiN coatings are characterized by nano-indentation and scratch tests. The friction and wear behaviors of these three coatings are evaluated by ball-on-disc tribological experiments under dry contact conditions.

The results show that the a-C:H coating has the highest coating-substrate adhesion strength (495 mN) and the smoothest surface (Ra is about 0.045 µm) compared with the other two coatings. The AlCrSiN coating shows the highest mean coefficient of friction (COF), whereas the ta-C coating exhibits the lowest one (steady at about 0.16). The carbon-based coatings possess excellent self-lubricating properties compared with nitride ceramic ones, which effectively reduce the COF by about 64%. The major failure mode of carbon-based coatings in dry contact is slight abrasive wear. The damage of AlCrSiN coating is mainly adhesive wear and abrasive wear.

It is suggested that the carbon-based film can effectively improve the friction-reducing and wear resistance performance of the gear steel surface, which has a promising application prospect in the mechanical transmission field.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0129/

The purpose of this paper is to study the cutting performance of high-speed regime end milling of AISI 4340 by investigating the tool life and wear mechanism of steel using the minimum quantity lubrication (MQL) technique to deliver the cutting fluid.

The experiments were designed using Taguchi L9 orthogonal array with the parameters chosen: cutting speed (between 300 and 400 m/min), feed rate (between 0.15 and 0.3 mm/tooth), axial depth of cut (between 0.5 and 0.7 mm) and radial depth of cut (between 0.3 and 0.7 mm). Toolmaker microscope, optical microscope and Hitachi SU3500 Variable Pressure Scanning Electron Microscope used to measure tool wear progression and wear mechanism.

Cutting speed 65.36%, radial depth of cut 24.06% and feed rate 6.28% are the cutting parameters that contribute the most to the rate of tool life. The study of the tool wear mechanism revealed that the oxide layer was observed during lower and high cutting speeds. The former provides a cushion of the protective layer while later reduce the surface hardness of the coated tool

A high-speed regime is usually carried out in dry conditions which can shorten the tool life and accelerate the tool wear. Thus, this research is important as it investigates how the use of MQL and cutting parameters can prolong the usage of tool life and at the same time to achieve a sustainable manufacturing process.

The paper aims to study the wear and breakage characteristics of coated carbide cutting tools through micro-milling slot experiments on superalloy Inconel 718.

During the micro-milling process, the wear and breakage appearance on the rake face and flank face of the cutting tools, as well as the failure mechanism, have been studied. Furthermore, the wear and breakage characteristics of the micro-cutting tools have been compared with the traditional milling on Inconel 718.

The main failure forms of the micro tool when micro-milling Inconel 718 were tool tip breakage and coating shed on the rake and flank faces of the cutting tool and micro-crack blade. The main causes of tool wear were synthetic action of adhesive abrasion, diffusion wear and oxidation wear, while the causes of abrasive wear were not obvious.

The changing trend in tool wear during the micro-milling process and the main reasons of the tool wear are studied. The findings will facilitate slowing down the tool wear and prolonging the tool life during micro-milling Inconel718.

The results of this paper can help slow down the tool wear and realize high efficiency, high precision and economical processing of small workpiece or structure of the nickel-based superalloy.

TiN and TiAlVN films have been prepared by DC magnetron sputtering technique at room temperature. TiN target has been used to deposit TiN thin film under pure argon (100 percent Ar) gas. Additionally, Ti6Al4V alloy target has been used to deposit TiAlVN under nitrogen and argon gas (50 percent Ar and 50 percent N₂). In this paper, two substrate types have been used: stainless steel 304 and Si(100). This analysis has confirmed that the nitride films, (TiN/Si) and TiAlVN in both cases, have been produced. Energy Depressive X-ray Spectroscopy (EDX) measurement confirmed that the TiN/Si was stoichiometry, where the N/Ti ratio was about 1 with low oxygen contamination. The results obtained have indicated that the TiAlVN has more resistance to corrosion than TiN film in 3.5 percent NaCl at 25°C (seawater). Both films, TiAlVN/SS304 and TiN/SS304, have shown improved corrosion resistance compared with virgin 304 substrate. Microhardness was carried out using Vickers method; the microhardness values for TiN/SS304 and TiAlVN/SS304 were approximately 7.5 GPa and 25.3 GPa, respectively. The paper aims to discuss these issues.

The films were prepared by a DC magnetron sputtering system starting from high pure (99.99 percent) Ti6Al4V target (Al 6wt%, V 4wt% and balance Ti) in plasma discharge argon/nitrogen (50 percent Ar and 50 percent N₂) for deposition of TiAlVN film. Pure TiN target (99.99 percent) was used for preparation of TiN film in pure argon plasma. The diameter of target was 50 mm and the power applied for preparation of the two films was 100 W. A cylindrical high-vacuum chamber (Figure 2) made of stainless steel 316, with height 363 mm diameter, was fabricated locally. Scanning electron microscope images have been used to discover the films morphology. The composition of the films has been determined by EDX technique for films deposited on Si substrate. The electrochemical corrosion test was carried out using conventional three-electrode cell of 300 ml capacity by using Voltalab PGZ 301 system (France) using Tafel extrapolation method and electrochemical impedance spectroscopy techniques.

TiN and TiAlVN films have been prepared by DC magnetron sputtering technique without heating of the substrates holder. The effects of the composition of nitride films on mechanical and corrosion properties were investigated. The composition of the films has been determined by EDX technique. The effect of using titanium alloy (Ti with Al and V) on the composition and crystalline quality has been investigated. The microhardness is strongly dependent on the addition of the Al and V elements, and it consequently improves mechanical proprieties. The microhardness values for TiN/SS304 were approximately 7.5 GPa and 25.3 GPa for TiAlVN/SS304. They indicate that prepared films prevent the aggressive action of corrosion media.

TiN and TiAlVN films have been prepared by DC magnetron sputtering method at room temperature. Titanium nitride film, especially TiAlVN, is an effective method to improve the corrosion resistance of SS304. TiAlVN film has exhibited enhanced corrosion resistance and higher microhardness. Independent time-of-flight elastic recoil detection analysis has been used to determine the composition of the film.

The present study spotlights the single and multicriteria decision-making (MCDM) methods to determine the optimal machining conditions and the predictive modeling for surface roughness (Ra) and cutting tool flank wear (VB) while hard turning of AISI 4340 steel (35 HRC) under dry environment.

In this study, Taguchi L16 design of experiments methodology was chosen. The experiments were performed under dry machining conditions using TiSiN-TiAlN nanolaminate PVD-coated cutting tool on which Taguchi and responses surface methodology (RSM) for single objective optimization and MCDM methods like the multi-objective optimization by ratio analysis (MOORA) were applied to attain optimal set of machining parameters. The predictive models for each response and multiresponse were developed using RSM-based regression analysis. S/N ratios, analysis of variance (ANOVA), Pareto diagram, Tukey's HSD test were carried out on experimental data for profound analysis.

Optimal set of machining parameters were obtained as cutting speed: at 180 m/min., feed rate: 0.05 mm/rev., and depth of cut: 0.15 mm; cutting speed: 145 m/min., feed rate: 0.20 mm/rev. and depth of cut: 0.1 mm for Ra and VB, respectively. ANOVA showed feed rate (96.97%) and cutting speed (58.9%) are dominant factors for Ra and VB, respectively. A remarkable improvement observed in Ra (64.05%) and VB (69.94%) after conducting confirmation tests. The results obtained through the MOORA method showed the optimal set of machining parameters (cutting speed = 180 m/min, feed rate = 0.15 mm/rev and depth of cut = 0.25 mm) for minimizing the Ra and VB.

This work contributes to realistic application for manufacturing industries those dealing with AISI 4340 steel of 35 HRC. The research contribution of present work including the predictive models will provide some useful guidelines in the field of manufacturing, in particular, manufacturing of gear shafts for power transmission, turbine shafts, fasteners, etc.

This paper aims to examine the performance of the machining parameters used in the hard-turning process of DIN 1.2738 mold steel and identify the optimum machining conditions.

Experiments were carried out via the Taguchi L18 orthogonal array. The evaluation of the experimental results was based on the signal/noise ratio. The effect levels of the control factors on the surface roughness and flank wear were specified with analysis of variance performed. Two different multiple regression analyses (linear and quadratic) were conducted for the experimental results. A higher correlation coefficient (R²) was obtained with the quadratic regression model, which showed values of 0.97 and 0.95 for Ra and Vb, respectively.

The experimental results indicated that generally better results were obtained with the TiAlN-coated tools, in respect to both surface roughness and flank wear. The Taguchi analysis found the optimum results for surface roughness to be with the cutting tools of coated carbide using physical vapor deposition (PVD), a cutting speed of 160 m/min and a feed rate of 0.1 mm/rev, and for flank wear, with cutting tools of coated carbide using PVD, a cutting speed of 80 m/min and a feed rate of 0.1 mm/rev. The results of calculations and confirmation tests for Ra were 0.595 and 0.570 µm, respectively, and for the Vb, 0.0244 and 0.0256 mm, respectively. Developed quadratic regression models demonstrated a very good relationship.

Optimal parameters for both Ra and Vb were obtained with the TiAlN-coated tool using PVD. Finally, confirmation tests were performed and showed that the optimization had been successfully implemented.