TiN Coated Carbide Tool Research Articles

Machinability of Aluminum Nitride Ceramic Using TiAlN and TiN Coated Carbide Tool Insert

This research presents the performance of Aluminum nitride ceramic in end milling using using TiAlN and TiN coated carbide tool insert under dry machining. The surface roughness of the work piece and tool wear was analyzed in this. The design of experiments (DOE) approach using Response surface methodology was implemented to optimize the cutting parameters of a computer numerical control (CNC) end milling machine. The analysis of variance (ANOVA) was adapted to identify the most influential factors on the CNC end milling process. The mathematical predictive model developed for surface roughness and tool wear in terms of cutting speed, feed rate, and depth of cut. The cutting speed is found to be the most significant factor affecting the surface roughness of work piece and tool wear in end milling process.

A comparative study on performance of multilayer coated and uncoated carbide inserts when turning AISI D2 steel under dry environment

The present work deals with a comparative study on flank wear, surface roughness, tool life, volume of chip removal and economical feasibility in turning high carbon high chromium AISI D2 steel with multilayer MTCVD coated [TiN/TiCN/Al2O3/TiN] and uncoated carbide inserts under dry cutting environment. Higher micro hardness of TiN coated carbide samples (1880HV) compared to uncoated carbide (1430HV) is observed and depicts better resistance against abrasion. The low erosion rate was observed in TiN coated insert compared to uncoated carbide. The tool life of TiN coated insert is found to be approximately 30times higher than the uncoated carbide insert under similar cutting conditions and produced lower surface roughness compared to uncoated carbide insert. The dominant wear mechanism was found to be abrasion and progression of wear was steady using multilayer TiN coated carbide insert. The developed regression model shows high determination coefficient i.e. R2=0.977 for flank wear and 0.94 for surface roughness and accurately explains the relationship between the responses and the independent variable. The machining cost per part for uncoated carbide insert is found to be 10.5times higher than the multilayer TiN coated carbide inserts. This indicates 90.5% cost savings using multilayer TiN coated inserts by the adoption of a cutting speed of 200m/min coupled with a tool feed rate of 0.21mm/rev and depth of cut of 0.4mm. Thus, TiN coated carbide tools are capable of reducing machining costs and performs better than uncoated carbide inserts in machining D2 steel.

Assessment of Process Parameters Influencing Delamination Factor on the Drilling of CFRC Composite Material with TiN Coated Carbide Tool

Assessment of Process Parameters Influencing Delamination Factor on the Drilling of CFRC Composite Material with TiN Coated Carbide Tool

Tool Wear Analysis in End Milling of Advanced Ceramics with TiAlN and TiN Coated Carbide Inserts

Advanced ceramic materials are difficult to machine by conventional methods due to the brittle nature and high hardness. The appropriate selection of cutting tool and cutting conditions may help to improve machinability by endmilling. Performance of TiAlN and TiN coated carbide tool insert in end milling of machinable glass ceramic has been investigated. Several dry cutting tests were performed to select the optimum cutting parameters for the endmilling in order to obtain better tool life. In this work, a study was carried out on the influence of cutting speed, feed rate and axial depth of cut on tool wear.The technique of design of experiments (DOE) was used for the planning and analysis of the experiments. Tool wear prediction model was developed using Response surface methodology.The results indicate that tool wear increased with increasing the cutting speed and axial depth of cut. Effect of feed rate is not much significant on selected range of cutting condition

On the existence of a thermal contact resistance at the tool-chip interface in dry cutting of AISI 1045: Formation mechanisms and influence on the cutting process

This paper questions the perfect thermal contact conditions usually assumed at the tool-chip interface in machining. Dry orthogonal cutting tests are first conducted on a AISI 1045 steel with TiN coated carbide tools. Tool-chip contact zones are analysed by SEM-EDS and sticking and sliding parts are dissociated. A formation mechanism of a Thermal Contact Resistance (TCR) is proposed from the real contact area extracted. A Finite Element (FE) model based on the Arbitrary-Lagrangian-Eulerian (ALE) approach is then employed to investigate the influence of such thermal contact conditions on the cutting process. Evolution of the main cutting outputs such as average cutting forces, average chip thickness, tool-chip contact length and thermal fields is assessed. It is demonstrated, on one side, that average cutting forces, chip thickness and tool-chip contact length are shown to be insensitive to a TCR. On the other side, heat flux transmitted to the tool, temperature distribution on the tool rake face as well as continuity of temperature across the tool-chip interface are clearly affected depending on its amplitude. This study emphasizes that the existence of a TCR at the tool-chip interface can completely modify local heat partition compared to a perfect thermal contact. The possible occurence of an imperfect contact in machining should be highly considered and modelled based on thermal exchange considerations. Local heat transfer models at the interface are still required to reach more reliable and physically based simulations.

CHARACTERIZATION OF FRICTION COEFFICIENT AND HEAT PARTITION COEFFICIENT BETWEEN AN AUSTENITIC STEEL AISI304L AND A TiN-COATED CARBIDE CUTTING TOOL

This work aims at characterizing the tribological behavior of an AISI304L austenitic steel and a TiN-coated carbide tool under extreme conditions corresponding to the one occurring at the cutting tool-work material in dry machining. A specially designed open tribometer has been used to characterize the friction coefficient, heat partition coefficient and adhesion in the contact versus sliding velocity and contact pressure. It has been shown that sliding velocity is the most influential parameter. An increase of sliding velocity induces a great decrease of friction coefficient, whereas contact pressure seems to play a secondary role on the friction coefficient. Adhesion is minimized when sliding speed increases. Heat partition coefficient decreases with sliding velocity, which tends to decrease the ratio of heat transmitted to cutting tools when sliding velocity increases. Finally, this work provides quantitative data of friction and heat partition coefficients versus sliding velocity and contact pressure in order to be implemented in any analytical or numerical cutting model.

Identification of a Friction Model at the Tool-Chip-Workpiece Interface in Dry Machining of a AISI 1045 Steel With a TiN Coated Carbide Tool

The characterization of frictional phenomena at the tool-chip-workpiece interface in metal cutting remains a challenge. This paper aims at identifying a friction model and a heat partition model at this interface during the dry cutting of an AISI1045 steel with TiN coated carbide tools. A new tribometer, based on a modified pin-on-ring system, has been used in order to reach relevant values of pressures, temperatures, and sliding velocities. Additionally a 3D Arbitrary Lagrangian Eulerian model (A.L.E.) numerical model simulating the frictional test has been developed in order to extract local parameters around the spherical pin, such as average contact pressure, average local sliding velocity, and average contact temperature, from experimental macroscopic measurements. A large range of sliding velocities [0.083–5 m/s] has been investigated. It has been shown that friction coefficient and heat partition coefficient are mainly dependant on local sliding velocity at the interface. Three friction regimes have been identified. These experimental and numerical results provide a better understanding of the tribological phenomena along the tool-chip-workpiece interfaces in dry machining of an AISI 1045 steel with a TiN coated carbide tool. Finally a new friction model and heat partition model has been developed for implementation in a numerical cutting model.

Experimental characterization of friction coefficient at the tool–chip–workpiece interface during dry cutting of AISI 1045

This paper presents the application of an experimental set-up able to simulate similar tribological phenomena as the ones occurring at the tool–chip–workpiece interface in metal cutting. Especially, this system enables to reach contact pressures up to 3GPa and sliding velocities between 0 and 300m/min. In addition to classical measurements of friction coefficients, the system provides information about the heat flux transmitted to pins, which enables to estimate the heat partition coefficient along the interface. This system has been applied to the characterization of the tool–chip–workpiece interface during dry cutting of an AISI 1045 steel with TiN coated carbide tools. It has been shown that the sliding velocity is the most influential parameter whereas contact pressure has only a limited influence. However, three friction regimes can be distinguished. In the first regime (low sliding velocity), friction coefficient is almost constant whereas heat flux transmitted to cutting tools is proportional to sliding velocity. In the second regime (intermediate sliding velocity), friction coefficient decreases very significantly with sliding velocity whereas heat flux remains almost constant. In the third regime (high sliding velocity), friction coefficient is not affected by sliding velocity whereas heat flux transmitted to the cutting tools increases again.

Effects of Lubrication Mode on Friction and Heat Partition Coefficients at the Tool–Work Material Interface in Machining

The quantification of friction coefficient along the tool–work material interface in machining remains an issue in tribology. This article aims at identifying the evolution of friction coefficient for a large range of sliding velocity during the machining of an AISI 4140 steel (290 HB) with a TiN-coated carbide tool. The influence of various lubricants (straight oil or emulsion) and lubrication modes (flow or mist) is investigated and compared to a dry sliding situation (dry machining). It has been shown that, in dry machining, the friction coefficient decreases with the sliding velocity until reaching a lower limit around 0.2. On the contrary, the presence of a straight oil significantly decreases friction coefficients to a value around 0.1. Emulsion enables a significant decrease of friction coefficient to around 0.2 for low sliding velocities, whereas its action is absent for higher sliding velocities. Oil mist exhibits an intermediate behavior. Finally, it has been shown that all kinds of lubrication lead to a large decrease of heat flux transmitted to cutting tools, even if heat flux is almost similar irrespective of the nature of oil and of its application mode. Straight oils decrease the heat flux transmitted to cutting tools due the decrease of friction coefficient, whereas they are not able to modify the heat partition coefficient at the interface. On the contrary, emulsions limit the transmission of heat flux to cutting tools due to their lower heat partition coefficient, even if their influence on friction is more limited.

Effects of a straight oil on friction at the tool–workmaterial interface in machining

The quantification of friction coefficient along the tool–workmaterial interface in machining remains an issue in tribology. This paper aims identifying the evolution of friction coefficient for a large range of sliding velocity during the machining of a AISI4140 steel (290 HB) with a TiN coated carbide tool. The influence of a straight oil is investigated compared to a dry sliding situation (dry machining). It has been shown that, in dry machining, friction coefficient decreases with the sliding velocity until reaching a downer limit around 0.2. On the contrary, the presence of a straight oil decreases significantly friction coefficients to a value around 0.1. Additionally, the friction coefficient becomes independent from the sliding velocity. It also been shown that a straight oil is able to penetrate the pin-workmaterial interface even if a very high contact pressure is present (∼3 GPa). The penetration duration is very fast, whereas its evacuation duration is much higher and strongly dependent on sliding speeds.

Macro-level environmental comparison of near-dry machining and flood machining

This paper focuses on investigating several aspects of the machining process from an ecological perspective, the result being a macro-level analysis. The analysis presented here considers not only the environmental impact of the material removal process itself, but also the impact of the associated processes such as the material preparation, and the scrap processing. A macro-level assessment of the comparative life cycle environmental performance of the near-dry machining (NDM) using TiN-coated carbide tools and the flood machining (FM) is performed by a case study referring to the gear milling. The assessment, using the SimaPro 7.1.5 software and the ecoinvent1.5 database, includes combined Life Cycle Assessment (LCA) of the workpiece material, the scrap processing, the use of lubrication, and the energy consumption.

Environment-Friendly Strategies for Efficient Utilization of Cutting Tools in Finish Turning

A number of experiments was conducted on the dry and air-cooled turning of steel with TiN coated carbide tool, and Weibull distribution was fitted on the tool life data. It is observed that the tool life (based on surface roughness) in dry turning is more than that in air-cooled turning. However, the tool consumed in air-cooled turning can be reused in dry turning. Further utilization of tool is possible by reusing the failed tool at reduced feed. These strategies of enhancing the tool life require only compressed air as a coolant, and hence, they are environment-friendly. A simple heuristic method is proposed for optimizing the finish turning process that is not dependent on a priori knowledge of tool life.

Surface roughness prediction based on the correlation between surface roughness and cutting vibrations in dry turning with TiN-coated carbide tools

This paper presents an approach to improving surface roughness prediction that is based on analysing cutting tool vibrations by a novel signal processing technique known as singular spectrum analysis (SSA). Each eigenvalue of the SSA decomposition of each vibration (radial, tangential, and feed vibration) and its corresponding principal component are studied and analysed to select only those eigenvalues of each vibration signal decomposition that contain valuable information for the development of a surface roughness prediction system (SRPS). Also, the influence of tool geometry and tool flank wear on the SSA decomposition of the vibrations is studied. Finally, only the information most correlated with surface quality, extracted by means of SSA of each vibration, is used to develop an SRPS. Experimental results provide conclusive support for the proposed SRPS, and justify the use of the SSA technique in the design of these systems. The ability of the SSA technique to extract only the information correlated with surface roughness of each cutting vibration and the manner in which tool geometry and tool flank wear influence the final Ra constitute the main contributions of this work.

Identification of a friction model—Application to the context of dry cutting of an AISI 1045 annealed steel with a TiN-coated carbide tool

The characterization of friction coefficients at the tool-chip-workpiece interface remains an issue. This paper aims to identify a friction model able to describe the friction coefficient at this interface during the dry cutting of an AISI1045 with TiN coated carbide tools. A new tribometer has been designed in order to reach relevant values of pressures and sliding velocities. This set-up is based on a modified pin-on-ring system. Additionally a numerical model simulating the frictional test has been associated in order to quantify average friction coefficients around the spherical pin, from the standard macroscopic data provided by the experimental system. A range of cutting speeds has been investigated. It has been shown that the friction coefficient is very much dependant on the sliding velocity. A new friction model has been identified based on the average local sliding velocity.

Identification of a friction model at tool/chip/workpiece interfaces in dry machining of AISI4142 treated steels

The characterization of frictional phenomena at the tool–chip–workpiece interface remains an issue. This paper aims to identify a friction model able to describe the friction coefficient at this interface during the dry cutting of a AISI4142 treated steel with TiN coated carbide tools. A new tribometer has been designed in order to reach relevant values of pressures, temperatures and sliding velocities. This set-up is based on a modified pin-on-ring system. Additionally a numerical model simulating the frictional test has been associated in order to identify local phenomena around the spherical pin, from the standard macroscopic data provided by the experimental system. A range of cutting speeds and pressures has been investigated. It has been shown that the friction coefficient is mainly dependant on the sliding velocity, whereas the pressure has a secondary importance. Moreover a new key parameter has been revealed, i.e. the average local sliding velocity at the contact. Finally a new friction model has been identified based on this local sliding velocity.

Development of a friction modelling method in dry cutting of AISI 316L austenitic stainless steels

This paper aims to identify a friction model able to describe the friction coefficient at the interface between the tool, the chip and workpiece during the dry cutting of a AISI316L austenitic stainless steel with TiN coated carbide tools. A new tribometer has been designed in order to reach relevant values of pressures, temperatures and sliding velocities. This set-up is based on a modified pin-on-ring system. Additionally a numerical model simulating the frictional test has been associated in order to identify local phenomena around the spherical pin, from the standard macroscopic data provided by the experimental system. It has been shown that the friction coefficient is mainly dependant on the sliding velocity, whereas the pressure has a secondary importance. Finally a new friction model has been identified based on this local sliding velocity.

Identification of a friction model—Application to the context of dry cutting of an AISI 316L austenitic stainless steel with a TiN coated carbide tool

The characterization of frictional phenomena at the tool–chip-workpiece interface remains an issue. This paper aims to identify a friction model able to describe the friction coefficient at this interface during the dry cutting of an AISI316L austenitic stainless steel with TiN coated carbide tools. A new tribometer has been designed in order to reach relevant values of pressures, temperatures and sliding velocities. This set-up is based on a modified pin-on-ring system. Additionally, a numerical model simulating the frictional test has been associated in order to identify local phenomena around the spherical pin, from the standard macroscopic data provided by the experimental system. A range of cutting speeds and pressures have been investigated. It has been shown that the friction coefficient is mainly dependant on the sliding velocity, whereas the pressure has a secondary importance. Moreover, a new key parameter has been revealed, i.e. the average local sliding velocity at the contact. Finally, a new friction model has been identified based on this local sliding velocity.

Modelling of friction phenomena in material removal processes

The understanding and modelling of friction phenomena is really important for modelling analytically and numerically the cutting operations. To perform measurement in extreme conditions such as machining conditions (high speeds, high pressures and high temperatures) a new generation of tribometer was designed. This experimental set up has been used to characterize the friction phenomena related to the machining of AISI 316L austenitic stainless steels with a TiN coated carbide insert. This paper presents a method used to obtain a new model for the friction coefficient. This process is divided into two steps. First the tribometer measures macroscopic forces induced in the pin. This is performed with various slipping speeds and forces applied on the pin to obtain a large range of macroscopic friction coefficients. These data are then used to build and load a scratching numerical model which is implemented in ABAQUS® EXPLICIT software to extract the local friction coefficient from the macroscopic scratching force ratios. In this paper, the experimental set up used to obtain the macroscopic results, the numerical model implemented in ABAQUS® EXPLICIT and the results concerning the friction between TiN coated carbide tools and AISI 316L during turning operations are described.

Effect of cutting speed on the performance of coated and uncoated cutting tools in turning nodular cast iron

This paper presents the results of an experimental investigation on the effect of cutting speed in turning nodular cast iron with coated and uncoated cutting tools. Three different carbide cutting tools were used, namely TiCN + TiC + TiCN + Al 2O 3 + TiN-coated carbide tools with multilayer coating of 7.5 and 10.5 μm thickness and uncoated WC/Co tool. Turning experiments were carried out at four different cutting speeds, which were 125, 150, 175 and 200 m/min. Feed rate ( f) and depth of cut ( a p) were kept fixed at 0.25 mm/rev and 1.5, respectively, throughout the experiments. Tool performance was evaluated with respect to tool wear, surface finish produced and cutting forces generated during turning. Uncoated WC/Co tool was the worst performing tool with respect to tool wear and was the worst with respect to surface finish. If tool wear, surface finish and cutting force results are considered together, among the three tools studied, 10.5 μm thick multilayer TiCN + TiC + TiCN + Al 2O 3 + TiN-coated carbide tool with external TiN layer is the most suitable one for turning nodular cast iron, especially at high cutting speeds.

Wear mechanism and failure mode of P10 TiN coated carbide tools

The wear mechanism and failure mode of TiN coated carbide tools were investigated at various combinations of cutting speed, feed rate and depth of cut for end milling of hardened AISI H13 tool steel. The cutting speed is used for semi finishing and finishing for the said material at high cutting speed regime. The rate of wear growth of the insert was assessed by progressive flank wear using an optical microscope. The wear mechanism and failure mode at the end of tool life on both the surface and underneath of the worn area was investigated in detail using optical microscope and Scanning Electron Microscope (SEM). The wear mechanism is predominantly controlled by the flank wear on the flank face with abrasion and adhesion were identified as a major contribution to tool failure.