Influence of coated tool electrode on drilling Inconel alloy 718 in Electrochemical micro machining

Since Inconel-718 alloy is high hardened material, it is very difficult to machine the alloy with complex shape using conventional machining process. In the present study, an endeavor has been made to drill the Inconel alloy 718 in micro level using electro chemical machining processes. It has been attempted to find the influence of coatings over copper tool electrode on performance criteria for enhancing the ECM process. From the experimental results, it has been observed that nickel coated copper electrode has produced 7.2% higher material removal whereas chromium coated electrode has produced 19% lower surface roughness over machined alloy specimens. (c) 2016 The Authors. Published by Elsevier B.V

Multi performance optimization of electrochemical micro-machining process surface related parameters on machining Inconel 718 using Taguchi-grey relational analysis

Due to several merits such as higher machining rate and high machining accuracy, electrochemical micromachining (ECMM) is used to machine high strength materials with complex shapes. In this experimental investigation, Inconel 718 specimens have been machined with brass electrode of 500 pm diameter using ECMM. Since electrochemical micromachining involves many responses, Taguchi method along cannot give to find out unique optimum parameter combination of the ECMM process. Therefore, an attempt has been made in the present study to identify the optimum combination of process parameter using grey relational analysis with Taguchi method. The experimental investigation of the process has been conducted with input process parameters such as applied voltage, electrolyte concentration, micro-tool feed rate and duty ratio on material removal rate (MRR), surface roughness (SR) and overcut (OC) with different process level using two electrolytes such as sodium chloride (NaCI) and sodium nitrate (NaNO3). From the experimental results, it has been found that micro-tool feed rate is most influencing nature parameter for NaCI and applied voltage is most influencing nature parameter for NaNO3 in ECMM process

Performance analysis of process variables on laser beam machining of inconel-718 alloy

Carbon-dioxide laser beam machining (LBM) is used for machining intricate shapes and hard materials which are inconceivable with conventional machining methods. Inconel 718 finds its prime applications in manufacturing high pressure turbine components and structural components of aerospace industry.Inconel 718 alloy exhibits superior physical and mechanical properties at elevated temperature, Strength-to-density ratio and higher corrosion resistance. The objective of the current work is to determine the optimal setting of the process parameters like laser power, cutting speed, gas pressure while machining Inconel-718 material using oxygen gas. The experiment was conducted using Taguchi L-9 orthogonal array. A square washer with four holes of diameter 8 mm and one hole of diameter 64 mm was machined using laser beam machining and the best combination of process parameters to acquire better response parameters is computed. The optimized value of surface roughness was found to be 3.5 mu m and similarly material removal rate to be 45.56 m(3)/min when operated at 2.1m/min cutting speed, cut of type rough, lmm of focal point and 4000bar gas pressure, The effect of input variables on various response parameters namely surface roughness (Ra), Heat affected zone thickness (HAZ), material removal rate (MRR), Taper, Circularity, hardness were studied. Morphology of the machined surface was investigated using SEM analysis

Comparison studies on mechanical and wear behavior of Stir Cast Al-SiC-B4C metal matrix composites

This paper studies the surface tribology and mechanical properties of AA6061 graded aluminum alloy matrix composite, reinforcing Silicon Carbide and Boron Carbide. In this work, the AA6061 graded aluminum alloy is reinforced with 3%, 6%, 9% (By weight) of B4C with constant 5% (By weight) of SiC under stir casting and producing three test samples A, B and, C respectively. The Samples were subjected to wear test, tensile test, impact test, and hardness test calculating wear loss, wear rate, coefficient of friction, ultimate tensile strength, impact strength, and brinell hardness. From analyzing the results from the test conducted, it is inferred that maintaining the optimum B4C composition between 3% and 6% in Al-SiC produces better mechanical properties and wear resistance

Experimental investigation of abrasive waterjet machining of Nickel based superalloys (Inconel 625)

This work explores abrasive waterjet machining (AWJM) process to improve the machining capabilities of conventional water jet machine by adding abrasive particles to the water jet. The addition of abrasive particles can turn the water jet into a modern machining tool for all materials. The experimental data of cutting parameters for hard-to-machine metal Inconel 625 is obtained. Inconel 625 is machined using an abrasive water jet and the effect of water pressure, abrasive flow rate, stand-off distance, surface quality has been studied and the response parameters are investigated. Experiments were conducted, based on Taguchi's L18 orthogonal array and the process parameters were optimized using Grey relational analysis. Further, the morphological study is made using scanning electron microscope (SEM) on the samples that were machined at optimized parameters. It is observed from the experiment that Stand-off distance is the most influencing parameter among the input parameters

Process parameter optimization of abrasive water jet machining on monel k400 alloy

Nowadays it's difficult to use a metal with high corrosion resistant properties in required applications. Monel 400 is one nickel based alloy having required property to be applicable in such scenarios. It is used in highly corrosive environments such as marine, chemical and aerospace industries as it has the property of maintaining its toughness over a range of temperature, however machining of this Monel alloy is relatively tough due to its characteristic work hardening properties. To tackle the mentioned issues, Abrasive water jet machining is used which is a widely known nontraditional machining technique. The process parameters and the response variables were chosen depending on the machine specifications, and parameter combinations were made using Minitab statistical software. The parameters and their interactions like the cut quality on the alloy, nozzle diameters effects, and water pressure were also studied. Response surface model and various statistical algorithms such as S-N ratio, ANOVA and regression equations were utilized for formation of the design of experiment, optimization of process parameters for the machining process were done using Grey relations. Reduction of surface roughness, maximization of Material removal rate while simultaneously reducing the cycle time for the operation was the primary objective. The results thus obtained indicates that the quality of cut was the most influential factor in the machining process followed by water-jet pressure value

Effect of Process Variables on Electrochemical Micromachining of Titanium Alloy (Ti-3Al-2.5V)

Electro-chemical Machining (ECM) is mainly used for shaping, deburring, milling and finishing operations in various precision industries and its use in micron level machining is called Electro-Chemical Micro Machining (EMM). EMM and ECM are receiving considerable attention from high-tech industries. It is because it allows to manufacture structures of complex shapes, it has high precision and accuracy, it is simpler and eco-friendly manufacturing technique and it can be used for different conducting materials. Different industry working with water which is saline, needs heat exchanger for the process. Titanium Alloy (Ti-3Al-2.5V) due to its high corrosion resistance under saline conditions is preferred by these industries. This present work is mainly concentrated on identifying the Material Removal rate (MRR) of Titanium Alloy (Ti-3Al-2.5V) workpiece by varying the process parameters like voltage, electrolyte concentration and duty cycle on electro-chemical micro machining

Performance Characteristics of Electrochemical Micromachining on Pure Titanium using coated tool electrode

Owing to its hardenable nature and corrosive resistant, Titanium is mainly utilized in fabricating turbine blade applications. Since it is very tough to creating the complex shape on this material by using traditional machining process. Generally micro holes are produced over the turbine blades to reduce the heat using EDM and LBM process. These processes can produce a heat affected zone over the machining surface and higher operating cost. The target of this present study was to make a micro hole on titanium by using electro chemical micro machining process and also attempt to identify the performance of nickel coated copper electrode for embellishing the ECM process. Since the process involves with no tool wear and less heat affect zone, it is possible to improve the machinability of the material. Titanium specimens have been machined using ECM process with uncoated copper electrode and nickel coated electrode under different process parameters combinations. From the experimental results, the better MRR and surface finish were observed from the nickel coated copper electrode

Processing and Testing of Epoxy Polymer Composites using Tender Palm Shoot Fiber and Aluminium Particles as Hybrid Reinforcements

Every year tons of plant and animal wastes are produced in the world. Some of these waste products may find some potential application in our day-to-day life. Also pure polymers are non-biodegradable and usually don’t possess requisite mechanical strength. For the first time, tender palm shoots are used as fiber reinforcement in the epoxy resin. The main objective is to compare and fabricate natural fiber reinforced hybrid epoxy composites with tender palm shoots, palymra fiber, as natural reinforcements which are generally leftovers and Aluminium powder as conductive filler by hand lay-up process at various weight percentages. Different mechanical properties, water absorption characteristics, flammability and electrical conductivity are evaluated as per ASTM standards. The test results show that these composites can be used as alternative materials for low tensile and high impact applications

Optimization of machining parameters on electrochemical micro machining of Hastelloy C22 using grey Taguchi method

Electro Chemical Machining (ECM) is a process that is used to machine extremely hard materials easily. It is a non-contact machining process. This ensures a higher tool life and no friction generated. The entire process is based on faradays laws of electrochemical process. With no heat affected zones (HAZ), this process holds a significant advantage over other high precision processes. This ensures that the material has neither thermal nor any other residual stresses. Nickel based alloys are known for their hardness and non-corrosive properties. This makes them unviable for machining using conventional methods as the overhead costs rise and makes them unproductive for use. ECM provides a better alternative comparatively. The alloy chosen for this analysis is Hastelloy C22. Its higher chromium content gives it better corrosion and pitting resistance. The objective of this analysis is to find the effects of various process parameters on MRR, surface finish, and dimensional deviation. The Taguchi technique has been used to investigate the effects of the ECMM process parameters and subsequently to predict sets of optimal parameters for maximum MRR and better surface finish. Grey analysis is done to find the optimal set of parameters for machining