Wear Mechanism of Multilayer Coated Carbide Cutting Tool in the Milling Process of AISI 4340 under Cryogenic Environment

Cryogenic technique is the use of a cryogenic medium as a coolant in machining operations. Commonly used cryogens are liquid nitrogen (LN2) and carbon dioxide (CO2) because of their low cost and non-harmful environmental impact. In this study, the effects of machining conditions and parameters on the wear mechanism were analysed in the milling process of AISI 4340 steel (32 HRC) under cryogenic conditions using a multilayer coated carbide cutting tool (TiAlN/AlCrN). A field emission scanning electron microscope with energy-dispersive X-ray analysis was used to examine the wear mechanisms comprehensively. At low machining parameters, abrasion and adhesion were the major wear mechanisms which occurred on the rake face. Machining at high machining parameters caused the removal of the coating material on the rake face due to the high temperature and cutting force generated during the cutting process. In addition, it was found that continuously adhered material on the rake face would lead to crater wear. Furthermore, the phenomenon of oxidation was also observed when machining at high cutting speed, which resulted in diffusion wear and increase in the crater wear. Based on the relationship between the cutting force and cutting temperature, it can be concluded that these machining outputs are significant in affecting the progression of tool wear rate, and tool wear mechanism in the machining of AISI 4340 alloy steel.

Hard Turning ASSESSMENT on EN31 Steel in Dry and Wet Cooling Environments USING Grey-Fuzzy Hybrid Optimization APPROACH

In recent years, machining of hard-to-cut metals by hard turning process is an embryonic technology for machining industry and research development. Hard turning is generally defined as the material removal process of hardened steel having hardness greater than 45 HRC. The current research presents a comparative hard turning investigation on EN 31 (56 ± 1 HRC) grade steel using physical vapor deposition (PVD) coated carbide tool under dry and wet cooling. The selection of a better cooling strategy among dry and wet cooling was based on the value of obtained surface roughness (Ra) and material removal rate (MRR) in hard turning. Wet cooling exhibited better performance over dry cutting as lower Ra and greater MRR are achieved with wet cooling. Further, considering Taguchi L16 orthogonal array, hard turning experiments were executed in wet cooling and responses like surface roughness (Ra), material removal rate (MRR), and diameter error were studied. Further, the Grey-fuzzy hybrid optimization tool was employed and found improved results relative to the alone grey relational analysis as about 9 % less Ra and 2.612 times more MRR is noticed at the grey fuzzy optimal set of parameters.

Dimensional analysis and ANN simulation of chip-tool interface temperature during turning SS304

Introduction. During machining, the resulting temperature has a wider and more critical impact on machining performance. During machining, the power consumption is mainly converted into heat near the cutting edge of the tool. Almost all the work performed during plastic deformation turns into heat. Researchers have put a lot of effort into measuring the cutting temperature during machining, as it significantly affects tool life and overall machining performance. The purpose of the work: to investigate the temperature of the chip-tool interface, taking into account the influence of cutting parameters and the type of tool coating during SS304 turning. The chip-tool interface temperature is measured by changing the cutting speed and feed with a constant cutting depth for uncoated and PVD single-layer TiAlN and multi-layer TiN/TiAlN coated carbide tools. In addition, an attempt is made to develop a model for predicting the temperature of the chip-tool interface using dimensional analysis and ANN simulating to better understand the process. The methods of investigation. Experiments are carried out with varying the cutting speed (140-260 m/min), feed (0.08-0.2 mm/rev) and a constant cutting depth of 1 mm. The chip-tool interface temperature is measured using the tool-work thermocouple principle. The Calibration Setup is designed to establish the relationship between the produced electromotive force (EMF) and the cutting temperature during machining. Statistical dimensional analysis and artificial neural network models have been developed to predict the temperature of the chip-tool interface. Tangential cutting force and chip attributes such as chip width and thickness are also measured depending on the cutting conditions, which is a prerequisite for dimensional analysis simulation. Results and Discussion. A tool made of TiAlN carbide with PVD coating had a lower temperature at the chip-tool interface than a tool with TiN/TiAlN coating. It has been observed that the chip-tool interface temperature increases prominently with the cutting speed, followed by the chip cross-sectional area and the specific cutting pressure. However, a lower cutting force was observed when using a carbide tool with a multi-layer TiN/TiAlN coating, which can be attributed to a lower coefficient of friction created by the front surface of this tool for flowing chips. On the other hand, the greatest cutting force was observed in uncoated carbide tools. It was noticed that the developed models allow predicting the temperature of the chip-tool interface with an absolute error of 5%. However, the lowest average absolute error of 0.78% was observed with the ANN model and, therefore, can be reliably used to predict the chip-tool interface temperature during SS304 turning.

VARIASI KECEPATAN PEMOTONGAN PROSES PEMBUBUTAN BAJA AISI 4140 TERHADAP KEAUSAN DAN UMUR MATA PAHAT KARBIDA

In the machining process, increased production can be done by increasing the use of cuttingparameters. However, the use of high cutting parameters has an effect on the wear of the cutting toolused. The aim of this research is to analyze the wear and tear that occurs on cutting tools and tool lifewhen cutting AISI 4140 steel by using variations in cutting speed. The machining process uses a CNClathe by turning the surface of the AISI 4140 steel workpiece. The wear criteria are determined when thecutting tool has reached the edge wear limit (VB) of 0.3 mm. Observation and measurement of carbidecutting tools are carried out every 5 minutes the machining process is carried out. If the cutting tool hasnot shown the specified wear value, then the cutting tool then cuts, so that the wear value is obtained.From the research conducted it was found that at a cutting speed of 160 m / min the cutting tool iscapable of cutting for 39 minutes, 13 seconds. At a cutting speed of 180 m / min the cutting tool is capableof cutting for 38 minutes, 14 seconds. At a cutting speed of 200 m / min the cutting tool is capable ofcutting for 33 minutes, 8 seconds. At a cutting speed of 240 m / min the cutting tool is capable of cuttingfor 26 minutes, 3 seconds. Taylor's advanced tool life for the coated carbide cutting tool in turning AISI4140 steel material is: Vc. Tl.0.073 = 8203.

Investigation of tool wear, surface roughness, sound intensity, and power consumption during hard turning of AISI 4140 steel using multilayer-coated carbide inserts

The present study investigated the machinability aspects, namely, surface roughness, sound intensity, power consumption, and crater wear, during dry turning of hardened AISI 4140 steel (63 HRC) employing (TiCN/Al2O3/TiN) multilayer-coated carbide inserts under dry cutting condition. The relationship between machining parameters and output parameters was determined using the Taguchi design. The analysis of variance was employed to evaluate the contributions of input parameters on output parameters. The main effect plots illustrated the impacts of cutting speed, feed, and depth of cut on response variables. Results show that the feed was the most dominant factor that affects surface roughness. Increasing the feed value increases the surface roughness, power consumption, and sound intensity. In the other part of this study, the constant values for feed (0.3 mm/rev), depth of cut (0.7 mm), and cutting speed (150 m/min) have been selected to evaluate a tool life that has 0.3 mm crater wear criteria. The results indicated that multilayer-coated carbide inserts presented very good tool life and reached 0.3 mm in 90 min. The experimental study results showed that chipping and abrasion were found to be the significant wear mechanism during hard turning of AISI 4140 steel. The cutting speed was the most significant parameter on the tool wear, although high cutting speed results the good surface finish but adversely increases the tool crater wear.

Evaluation of: MOSSA, MOALO, MOVO and MOGWO Algorithms in Green Machining for High Production Performance in Turning of X210Cr12 Steel

The current study investigates the Wet and MQL machining, when turning of X210Cr12 steel, using a multilayer-coated carbide insert (GC-4215) with various nose radius, the consideration of the tool geometry with different cooling modes allow as to assess the comportment of the machined steel against the cutting combinations. The response surface methodology (RSM) has been used for regression analysis and to evaluate the contribution of the cutting parameters on surface roughness, tangential force and cutting power using ANOVA analysis. The developed models have been used to predict the studied output factors according to the selected cutting parameters for wet and MQL machining. A comparative between the cooling techniques have been established to determine the most effective technique in terms of part quality, lubricant consumption and power consumption. Finally, four new optimization technics have been used for the process optimization using the MQL models for an environment-friendly machining.