Investigating Microstructural Changes and Phase Transformation During Slot Milling of Ti-6Al-4V in Dry, Flood Coolant and MQL Conditions

2019 ◽  
Author(s):  
Ashutosh Khatri ◽  
Muhammad P. Jahan ◽  
Xingbang Chen ◽  
Jianfeng Ma
Keyword(s):  
Phase Transformation ◽  
Cutting Speed ◽  
Thermal Softening ◽  
Phase Changes ◽  
Depth Of Cut ◽  
Dry Machining ◽  
Machined Surface ◽  
Microstructural Changes ◽  
Slot Milling ◽  
Β Phase

Abstract The objective of this study is to investigate the microstructural changes and phase transformation of chips and workpiece during slot milling on Ti-6Al-4V alloy in dry, flood coolant, and MQL conditions using uncoated carbide tools. The experiments were performed at varying feed rate and depth of cut with a fixed cutting speed of 50 m/min. The microstructures of the machined chips indicate that dry machining had the highest percentage of β-phase indicating higher phase transformation owing to higher tool temperature. The β-phase was found to be the least in MQL machining chips, which is very similar to the microstructural composition of un-machined surface. Although there were signs of phase transformation, there were very minimal changes in phases in the workpiece for all three machining conditions. In many cases, no change or slight decrease in β-phase was observed at the sub-surface, indicating thermal softening of the workpiece, especially in dry machining. The findings from this study confirm the fact that, high temperature close to beta transition temperature is generated during dry machining of titanium alloy, and most of heat is carried away by the chips resulting in phase transformation from alpha to beta phase in chips. However, no significant phase changes occurred into the microstructure of the workpiece in any condition, although minor thermal softening was found at the sub-surface of dry machined workpiece.

Thermal hardening and calculation of the mathematical model of face milling of parts made of steel 95X18-Sh to improve the quality of the surface layer

2021 ◽  
pp. 200-206
Author(s):  
I.N. Sedinin ◽  
V.F. Makarov
Keyword(s):  
Mathematical Model ◽  
Cutting Speed ◽  
Physical And Mechanical Properties ◽  
Face Milling ◽  
Experiment Planning ◽  
Depth Of Cut ◽  
Machined Surface ◽  
The Mathematical Model ◽  
Full Factorial

It is considered the complex of operations of the technological process for the heat treatment of steel 95X18-Sh, as a result of which the material of the samples increases the hardness to 59...61 HRC, and also improves the physical and mechanical properties. A full-scale full factorial experiment of face milling of samples was carried out using the method of mathematical planning. In the experiments, a high-precision machine and a carbide cutting tool were used. To calculate the values of the roughness function, the following are taken as independent variables: cutting speed, feed per tooth and depth of cut. In order to determine the coefficients of the linear equation, a central compositional orthogonal plan of the second order for three factors was used. A matrix of levels of variation of independent variable factors and a matrix of experiment planning were compiled. A regression analysis of the obtained experimental statistical data was carried out using the Microsoft Excel, Statistica and Wolfram Alpha programs. As a result of the calculations, a mathematical model of the roughness of the machined surface and optimal cutting conditions were determined.

Performance assessment of energy efficient and eco-friendly turning of Nimonic C-263: A comparative study on MQL and cryogenic machining

2021 ◽  
pp. 095440542110619
Author(s):  
Prashant S Jadhav ◽  
Chinmaya P Mohanty
Keyword(s):  
Work Environment ◽  
Manufacturing Industry ◽  
Cutting Speed ◽  
Machining Process ◽  
Depth Of Cut ◽  
Work Piece ◽  
Cryogenic Machining ◽  
Machined Surface ◽  
Machining Strategies ◽  
The Impact

Nimonic C-263 is predominantly used in the manufacturing of heat susceptible intricate components in the gas turbine, aircraft, and automotive industries. Owing to its high strength, poor thermal conductivity, the superalloy is difficult to machine and causes rapid tool wear during conventional machining mode. Moreover, the unpleasant machining noise produced during machining severely disrupts the tool engineer’s concentration, thereby denying a precise and environment friendly machining operation. Hence, close dimensional accuracy, superior machined surface quality along with production economy, and pleasant work environment for the tool engineers is the need of an hour of the current manufacturing industry. To counter such issues, the present work attempts to compare and explore the machinability of two of the most popular machining strategies like minimum quantity lubrication (MQL) and cryogenic machining process during turning of Nimonic C-263 work piece in order to achieve an ideal machining environment. The machining characteristics are compared in terms of surface roughness (SR), power consumption (P), machining noise (S), nose wear (NW), and cutting forces (CF) to evaluate the impact of machining variables like cutting speed (Vc), feed (f), and depth of cut (ap) with a detailed parametric study and technical justification. Yet again, an investigation is conducted to compare both the machining strategies in terms of qualitative responses like chip morphology, total machining cost, and carbon emissions. The study revealed that cryogenic machining strategy is adequately proficient over MQL machining to deliver energy proficient and gratifying work environment for the tool engineers by reducing the cost of machining and improving their work efficiency.

Effect of Cutting Temperature on Phase Transformation in Cutting of NiTi Alloy

2020 ◽  
Author(s):  
Hao Yang ◽  
Katsuhiko Sakai ◽  
Hiroo Shizuka ◽  
Kunio Hayakawa ◽  
Tetsuo Nagare
Keyword(s):  
Phase Transformation ◽  
Phase State ◽  
Niti Alloy ◽  
Cutting Temperature ◽  
Cutting Speed ◽  
Cutting Process ◽  
Maximum Temperature ◽  
Machined Surface ◽  
Speed Condition ◽  
Work Material

Abstract In this study, the effect of cutting temperature on phase transformation in cutting of room temperature austenitic NiTi alloy was investigated by X-ray diffraction (XRD) and temperature measurements. Results from XRD reveals that after cutting process, the phase state of work material near the machined surface transformed from austenite to martensite at relatively low cutting speed conditions while the phase state of work material did not undergo any form of transformation at the highest cutting speed condition. Temperature measurement results measured with temperature indicating paint showed that the maximum temperature of work material near the machined surface in cutting process exceeded the Md temperature at the highest cutting speed condition. However, there was no phase transformation observed in cutting chips after cutting at all cutting speed conditions as the temperature of cutting chips was much higher than the Md temperature under all cutting speed conditions.

EVALUATION OF SURFACE ROUGHNESS PRODUCED BY NANOCUTTING COPPER STRUCTURE USING A LEAST SQUARE MEAN METHOD

2019 ◽  
Vol 27 (01) ◽  
pp. 1950081 ◽  
Author(s):  
CHUNHUI JI ◽  
SHUANGQIU SUN ◽  
BIN LIN ◽  
TIANYI SUI
Keyword(s):  
Surface Roughness ◽  
Cutting Speed ◽  
Least Square ◽  
Depth Of Cut ◽  
Real Surface ◽  
Roughness Parameters ◽  
Machined Surface ◽  
Surface Roughness Parameters ◽  
3D Surface ◽  
3D Surface Roughness

This work performed molecular dynamic simulations to study the 2D profile and 3D surface topography in the nanometric cutting process. The least square mean method was used to model the evaluation criteria for the surface roughness at the nanometric scale. The result showed that the cutting speed was the most important factor influencing the spacing between the peaks, the sharpness of the peaks, and the randomness of the profile. The plastic deformation degree of the machined surface at the nanometric scale was significantly influenced by the cutting speed and depth of cut. The 2D and 3D surface roughness parameters exhibited a similar variation tendency, and the parameters Ra and Rq tended to increase gradually with an increase in the cutting speed and a decrease in the depth of cut. Finally, it is concluded that at the nanometric scale, the 3D surface roughness parameters could more accurately reflect the real surface characteristics than the 2D parameters.

scholarly journals Investigation of AlCrN-Coated Inserts on Cryogenic Turning of Ti-6Al-4V Alloy

Metals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1338
Author(s):  
Lakshmanan Selvam ◽  
Pradeep Kumar Murugesan ◽  
Dhananchezian Mani ◽  
Yuvaraj Natarajan
Keyword(s):  
Tool Wear ◽  
Cutting Force ◽  
Physical Vapor Deposition ◽  
Metal Cutting ◽  
Cutting Speed ◽  
Depth Of Cut ◽  
Machining Parameters ◽  
Machined Surface ◽  
Coated Carbide ◽  
Cryogenic Conditions

Over the past decade, the focus of the metal cutting industry has been on the improvement of tool life for achieving higher productivity and better finish. Researchers are attempting to reduce tool failure in several ways such as modified coating characteristics of a cutting tool, conventional coolant, cryogenic coolant, and cryogenic treated insert. In this study, a single layer coating was made on cutting carbide inserts with newly determined thickness. Coating thickness, presence of coating materials, and coated insert hardness were observed. This investigation also dealt with the effect of machining parameters on the cutting force, surface finish, and tool wear when turning Ti-6Al-4V alloy without coating and Physical Vapor Deposition (PVD)-AlCrN coated carbide cutting inserts under cryogenic conditions. The experimental results showed that AlCrN-based coated tools with cryogenic conditions developed reduced tool wear and surface roughness on the machined surface, and cutting force reductions were observed when a comparison was made with the uncoated carbide insert. The best optimal parameters of a cutting speed (Vc) of 215 m/min, feed rate (f) of 0.102 mm/rev, and depth of cut (doc) of 0.5 mm are recommended for turning titanium alloy using the multi-response TOPSIS technique.

Investigation of Surface Characteristics and Chip Morphology in High Speed Cutting of Inconel718 Based on SHPB System

2019 ◽  
Author(s):  
Zengqiang Wang ◽  
Zhanfei Zhang ◽  
Wenhu Wang ◽  
Ruisong Jiang ◽  
Kunyang Lin ◽  
...  
Keyword(s):  
Surface Roughness ◽  
High Speed ◽  
Split Hopkinson Pressure Bar ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Surface Profile ◽  
Chip Morphology ◽  
Depth Of Cut ◽  
Machined Surface ◽  
High Speed Cutting

Abstract High speed cutting (HSC) technology has the characteristics of high material removal rates and high machining precision. In order to study the relationships between chip morphology and machining surface characteristic in high speed cutting of superalloy Inconel718. High-speed orthogonal cutting experiment are carried out by used a high speed cutting device based on split Hopkinson pressure bar (SHPB). The specimen surfaces and collected chips were then detected with optical microscope, scanning electron microscope and three-dimensional surface profile measuring instrument. The results show that within the experimental parameters (cutting speed from 8–16m/s, depth of cut 0.1–0.5mm), the obtained chips are sawtooth chips and periodic micro-ripple appear on the machined surface. With the cutting speed increases, machining surface roughness is decreases from 1.4 to 0.99μm, and the amplitude of periodic ripples also decreases. With the cutting depth increases, the machining surface roughness increases from 0.96 to 5.12μm and surface topography becomes worse. With the increase of cutting speed and depth of cut, the chips are transform from continues sawtooth to sawtooth fragment. By comparing the frequency of surface ripples and sawtooth chips, it is found that they are highly consistent.

Machining characteristics of Inconel 718 under several cutting conditions based on Taguchi method

2012 ◽  
Vol 227 (9) ◽  
pp. 1889-1897 ◽  
Author(s):  
R Thirumalai ◽  
JS Senthilkumaar ◽  
P Selvarani ◽  
S Ramesh
Keyword(s):  
Surface Roughness ◽  
Inconel 718 ◽  
Flank Wear ◽  
Optimization Technique ◽  
Cutting Speed ◽  
Depth Of Cut ◽  
Cutting Condition ◽  
Machining Parameters ◽  
Dry Machining ◽  
Noise Factors

Extensive researchers have conducted several experiments in the past for selecting the optimum parameters in machining nickel based alloy – Inconel 718. These experiments conducted so far are dealt with dry machining and flooded coolant machining of nickel alloy Inconel 718. In this research study, the usage of refrigerated coolant is also dealt with and it is compared with dry machining and flooded coolant machining. Cutting speed, feed and depth of cut are considered as the machining parameters. The effectiveness of the refrigerated coolant in machining the heat resistant super alloy material Inconel 718 with respect to these machining parameters are described in this article. The machinability studies parameters were generated with surface roughness and flank wear. The performance of uncoated carbide cutting tool was investigated at various cutting condition under dry, flooded coolant and refrigerated coolant machining. The relationship between the machining parameters and the performance measures were established and using analysis of variance significant machining parameters determined. This article made an attempt to Taguchi optimization technique to study the machinability performances of Inconel 718. Taguchi approach is an efficient and effective experimental method in which a response variable can be optimized, given various control and noise factors, using fewer experiments than a factorial design. Taguchi’s optimization analysis indicates that the factors level, its significance to influence the surface roughness and flank wear for the machining processes. Confirmation tests were conducted at an optimal condition to make a comparison between the experimental results foreseen from the mentioned correlations.

scholarly journals Experimental Investigation on Surface Roughness and Tool Wear in Dry Machining of TiC Reinforced Aluminium LM6 Composite

2013 ◽  
Vol 773-774 ◽  
pp. 339-347 ◽  
Author(s):  
Muhammad Yusuf ◽  
M.K.A. Ariffin ◽  
N. Ismail ◽  
S. Sulaiman
Keyword(s):  
Surface Roughness ◽  
Tool Wear ◽  
Feed Rate ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Depth Of Cut ◽  
Carbide Tool ◽  
Dry Machining ◽  
Workpiece Surface ◽  
High Cutting Speed

With increasing quantities of applications of Metal Matrix Composites (MMCs), the machinablity of these materials has become important for investigation. This paper presents an investigation of surface roughness and tool wear in dry machining of aluminium LM6-TiC composite using uncoated carbide tool. The experiments carried out consisted of different cutting models based on combination of cutting speed, feed rate and depth of cut as the parameters of cutting process. The cutting models designed based on the Design of Experiment Response Surface Methodology. The objective of this research is finding the optimum cutting parameters based on workpiece surface roughness and cutting tool wear. The results indicated that the optimum workpiece surface roughness was found at high cutting speed of 250 m min-1 with various feed rate within range of 0.05 to 0.2 mm rev-1, and depth of cut within range of 0.5 to 1.5 mm. Turning operation at high cutting speed of 250 m min-1 produced faster tool wear as compared to low cutting speed of 175 m min-1 and 100 m min-1. The wear minimum (VB = 42 μm ) was found at cutting speed of 100 m min-1, feet rate of 0.2 mm rev-1, and depth of cut of 1.0 mm until the length of cut reached 4050 mm. Based on the results of the workpiece surface roughness and the tool flank wear, recommended that turning of LM6 aluminium with 2 wt % TiC composite using uncoated carbide tool should be carried out at cutting speed higher than 175 m min-1 but at feed rate of less than 0.05 mm rev-1 and depth of cut less than 1.0 mm.

RSM Based Investigations on the Effects of Cutting Parameters on Surface Integrity during Cryogenic Hard Turning of AISI 52100

2015 ◽  
Vol 15 (3) ◽  
pp. 309-318 ◽  
Author(s):  
Suha K. Shihab ◽  
Zahid A. Khan ◽  
Arshad Noor Siddiquee
Keyword(s):  
Surface Integrity ◽  
Feed Rate ◽  
Hard Turning ◽  
Desirability Function ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Depth Of Cut ◽  
Machined Surface ◽  
Aisi 52100 ◽  
Model Equations

AbstractEffect of cryogenic hard turning parameters (cutting speed, feed rate, and depth of cut) on surface roughness (Ra) and micro-hardness (µH) that constitute surface integrity (SI) of the machined surface of alloy steel AISI 52100 is investigated. Multilayer hard surface coated (TiN/TiCN/Al2O3/TiN) insert on CNC lathe is used for turning under different cutting parameters settings. RSM based Central composite design (CCD) of experiment is used to collect data for Ra and µH. Validity of assumptions related to the collected data is checked through several diagnostic tests. The analysis of variance (ANOVA) is used to determine main and interaction effects. Relationship between the variables is established using quadratic regression model. Both Ra and µH are influenced principally by the cutting speed and the feed rate. Model equations are found to predict accurate values of Ra and µH. Finally, desirability function approach for multiple response optimization is used to produce optimum SI.

Fuzzy Modeling and Analysis on the Turning Parameters for Machining Force and Specific Cutting Pressure in CFRP Composites

2013 ◽  
Vol 766 ◽  
pp. 77-97
Author(s):  
T. Rajasekaran ◽  
V.N. Gaitonde ◽  
J. Paulo Davim
Keyword(s):  
Fuzzy Logic ◽  
Composite Materials ◽  
Prediction Models ◽  
Cutting Speed ◽  
Depth Of Cut ◽  
Machining Parameters ◽  
Machined Surface ◽  
Sem Images ◽  
Machining Force ◽  
Soft Computing Techniques

Analysis of the cutting force and specific cutting pressure play vital roles in machining of the composite materials. The present experimental work describes the modeling of machining parameters using one of the soft computing techniques i.e. fuzzy logic for machining force and specific cutting pressure. The basic idea is to machine the carbon fiber reinforced plastic (CFRP) composite materials and measuring the cutting forces and then determining the machining force and specific cutting pressure. 27 experiments based on Taguchis L27 orthogonal array were carried out involving three machining parameters, namely, cutting speed, feed and depth of cut, each defined at three levels. Subsequently the prediction models were developed using three different fuzzy logic membership functions, namely, triangular, trapezoidal and bell shape. It is found that the predicted values of proposed responses such as machining force and specific cutting pressure are very close to the experimental values within the chosen ranges of the process parameters. The statistical analysis using ANOVA on machining parameters are also presented and discussed. The machined surface analyzed through SEM images revealed the damages encountered during turning process.

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