This study focused on experimental investigation and optimisation of laser aided hybrid machining of Inconel 718 alloy. Cutting speed, feed rate and laser power are varied each at three levels and total of 27 experiments are conducted. Cutting force, surface roughness and flank wear are measured. The factor effects on each response are analysed using 3D surface plot. The developed regression model shows good degree of fit. From the analysis of variance, the feed rate and laser power are influencing parameters on the cutting force and surface roughness while cutting speed is for tool wear. The optimal process parameter setting using desirability analysis reveals a reduction of cutting force by 50%, surface roughness by 26%, flank wear by 33% and the tool life is extended up to 133% over conventional machining. The segmentation of saw tooth chip is increased which demonstrated the thermal softening effect compared to conventional machining. © 2016 Inderscience Enterprises Ltd.

Venkatesan K

Department of Design and Automation

School of Mechanical Engineering

Vellore Campus

Ramanujam R

Department of Manufacturing Engineering

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Optimisation of machining parameters in laser aided hybrid machining of Inconel 718

International Journal of Machining and Machinability of Materials

The study is focussed on the comparative performance of input-parameters on cutting force, roughness, tool wear, and chip morphology of sustainable conditions (dry and MQL: Minimum quantity lubrication) on Nimonic 90 alloy. 0.25 wt% of nano hexagonal boron nitride (hBN) mixed with groundnut oil is used as nanofluids, and experimentations are accomplished on Taguchi's L16 orthogonal array. Results show that in nano-MQL, the improvement of 1.654 and 1.276 times, 4.522, and 2.196 times that dry with two coated carbide insert for force and roughness. Coating loss occurred under the nano-MQL mode, whereas abrasion, notching observed in dry machining. The chip thickness ratio were1.34 times and 1.77 times, the shear angle was 1.22 times and 1.61 times, and reduced coefficient of friction under nano-MQL compared to dry. Nano-MQL with chemical vapour deposition (CVD) carbide insert is suitable for machining of alloy 90 with improved performance characteristics that of other machining conditions. © 2019 Elsevier Ltd

Measurement

Investigation of machinability characteristics and comparative analysis under different machining conditions for sustainable manufacturing

Inconel 617 alloy is corrosion and oxidation resistant, nickel-based alloy and emanates under tough to turn material. Moreover, turning off this alloy under MQL need attention. In this context, this work aims to examine the machinability study under MQL on CNC turning of 617 alloys by AlTiN PVD carbide cutting inserts. As a methodology, the Taguchi L9 orthogonal array parameter design and response surface optimization has been employed. 1D and 3D plots have been used to analysis on the collected machining data based on fitted regression model. The statistical analysis revealed % concentration impacted for force, cutting velocity influenced for surface roughness and tool wear. From the optimization analysis, 0.25% Al2O3 Nano-fluid in coconut oil along with a cutting speed of 40 m/min and 0.14 mm/rev feed rate. Abrasion, adhesion and diffusion wear are identified as wear mechanisms. The diameter of produced helical and tubular chips are different, and at high % concentration, the curl diameter is found to be increased due to the decrease in lubricity and increase tool friction on turning of Inconel 617. © 2019 The Authors. Published by Elsevier Ltd.

Fulltext

Procedia Manufacturing

Machinability study and multi-response optimization of cutting force, Surface roughness and tool wear on CNC turned Inconel 617 superalloy using Al2O3 Nanofluids in Coconut oil

This paper presents the parametric study, process benefits, optimization and chip appearance of machining parameters on turning of the Inconel 718 using Nd: YAG laser source. To analyze the mentioned above effect on alloy 718, the cutting inserts of chemical vapor disposition coated (CVD) TiN/TICN/Al2O3 are used to turn at the time of machining. To evaluate the linear (mean effect plots) and interaction effect (3D surface plots) of laser parameters on the force, roughness and tool wear to keep the minimal, experiments of the L27 orthogonal array are done by selecting the controllable parameters viz speed, the rate of feed along with laser power. From the parametric study, increase in speed and laser power along with decrement in the rate of feed resulted in lower cutting force. But surface finish and tool wear reduced with a decline in speed and scale of feed and increased with increment in laser power. The investigations result in shows that with the application of moderate laser power decline the cutting force by 28%; both surface roughness along with flank wear by 60% that of CM. Results of variance test show that the speed along with the rate of feed bags the critical effect on the force, roughness, and tool wear followed by laser power. Desirability function analysis (DFA) is employed as response optimizer to determine optimum levels which minimize force, roughness as well as flank wear. At the determined optimum conditions compared to CM, 66% increment in the tool life is obtained in LAT. The presence of abrasion and flaking while the absence of chipping is observed in LAT compared to CM using an optical image. Under chip appearance, the benefit is determined due to the maximum un-deformed chip thickness of about 130 μm in LAT compared to CM. © 2018 SAE International. All Rights Reserved.

SAE Technical Paper Series

Parametric Study, the Process Benefits, Optimization and Chip Morphology Study of Machining Parameter on Turning of Inconel 718 Using CVD Coated Tool and Nd: YAG Laser

Inconel 718 is a representative of high temperature alloy which poses substantial difficulties in machining processes. High strength, high cutting temperature and a subsequent work hardening during machining process adversely affect the cutting force, surface integrity, tool life and chip breakability. The above difficulties have been disproving by employing the Laser Assisted Machining (LAM). LAM is a hybrid technique and used to machining the work-piece with conventional tool after softening it with laser emitted heat. An attempt has been made in the present study for an experimental investigation on the machining attributes of 718 Inconel super alloy during laser assisted machining using uncoated carbide insert. Experimental plan is designed based on Taguchi's L18 mixed orthogonal array of design of experiment. Three response values such as cutting force, surface roughness and tool wear are measured and their effects are studied. The variability due to the machining parameters are dispensed using variance test. Predictive regression equations are developed for the estimation of all the quality characteristics. Also the Pearson correlation coefficient analysis is calculated to analyze the correlation between the input parameters and quality characteristics. Results showed a strong correlation between the feed rate and the cutting force and surface roughness followed by cutting speed. The results obtained from experiments are analyzed to predict the optimal machining conditions using desirability approach. At the optimal laser parameters, the tool life, when laser beam is used, is improved by 9% compared to conventional machining. © 2017 Elsevier Ltd.

Materials Today: Proceedings

Estimation of Optimal Laser Parameters On Inconel 718 By Taguchi Methodology

Laser-assisted machining (LAM) is a new method and actively researched for various difficult to machine materials. In LAM, machining is carried after prediction of material removal temperature (preheating temperature) for material with fixed cutting depth using a laser source. Among the various difficult-to-cut materials, Inconel 718, nickel-based super alloys, is difficult to machine due high strength at elevated temperature and low thermal conductivity. Studies on machining of Inconel 718 using a laser has been performed for various position of laser source to reveal the process benefits of Inconel 718 with fixed cutting depth. But there are no studies and results on prediction of heat affected depth for preheating temperature using laser assisted machining of Inconel 718 on various laser beam angle. So, in the present study, the effect of application of laser when applied at different angles is studied by two different methods-one with offset and other without offset. Finite element method is used to perform the simulations. This contribution brings a new novelty to the present research work on metal cutting domain using laser. The heat affected depth was also found and compared with depth obtained through experiments. And, the error percentage found for heat affected depth and preheating temperature is about 11%. The experimental results reveal that laser beam at an angle of 60°has maximum depth of cut, while minimum depth of cut is found at 90°. © 2017 Elsevier Ltd.

A study on preheating temperature and heat affected depth according to various laser beam angle for laser-assisted machining

Machining parameters optimisation in turning of GFRP composites by desirability function analysis embedded with Taguchi method

Optics & Laser Technology

An experimental investigation of pulsed laser-assisted machining of AISI 52100 steel

International Journal of Precision Engineering and Manufacturing

A study on the laser preheating effect of inconel 718 specimen with rotated angle with respect to 2-axis

International Journal of Machine Tools and Manufacture

Mechanisms involved in the improvement of Inconel 718 machinability by laser assisted machining (LAM)

The International Journal of Advanced Manufacturing Technology

The influence of laser assistance on the machinability of the titanium alloy Ti555-3

Journal	International Journal of Machining and Machinability of Materials
Publisher	Inderscience Publishers
ISSN	1748-5711
Open Access	No