Effect Of Machining Process Parameters Research Articles

Force evaluation and machining parameter optimization in milling of aluminium burr composite based on response surface method

ABSTRACT A significant measure for improving surface quality and workpiece machining efficiency is an optimisation of cutting parameters in millings. To increase machining capacities, the investigation of friction forces prediction plays a positive role. A rotatable centre composite experiment with abrasion of flat/slot in aluminium working part was developed to determine cutting forces to enhance cutting parameter, feed per tooth (ft), axial cutting depth (ad), speed of spindle (n), and length of tool (lt) based on methods of reaction of the second-order surface. To determine the regression model referring to cutting parameters, the least-squares procedure was used during the experimental results. At the same time, a friction prediction model has been developed and the parameters are calculated to eventually enhance the experimental values. ANOVA checked the estimated regression Eqn s and analysed the effect of machining process parameters on the morphology of force and topmost burrs. The results of the experiment show that ad and ft have an important milling force and width of top burrs in a certain range of cutting parameters. Optimised cutting parameters are: n is 1000 r per minute; ap is 5 μm, and l is 15.2 mm, ft is 3 μm/z according to optimum response value.

Investigation of surface integrity in the laser-assisted turning of AISI 4340 hardened steel

The use of laser-assisted turning (LAT) can improve different aspects of the machinability of high hardness/strength materials. The heat applied in this process reduces the strength of the material and upon a proper selection of laser heat source and machining process parameters, a significant improvement in the machining process can be achieved. This research studies the effect of machining and laser heat source parameters on the surface integrity of the LAT process of AISI 4340 hardened steel with a hardness of 560 HV using Response Surface Methodology (RSM). The effect of machining process parameters (feed rate, depth of cut and cutting speed) and laser power on the surface integrity characteristics of the machined surfaces (white layer thickness, microhardness, surface roughness, and surface chemical composition) are investigated. A detailed finite element simulation of the process has been performed to better understand the physics of the process and to interpret the experimental results. Laser power and feed rate are shown to be the most significant parameters affecting the surface integrity of the machined surfaces. It has been shown that a proper selection of machining and laser heat source parameters makes it possible to minimize the adverse effect of laser heating in the LAT process. This can pave the way for the widespread application of the LAT process by eliminating one of the most important obstacles of this process by controlling the laser heat diffusion into the workpiece.

Investigation on MRR and DOC of the micro-holes generated on quartz using silicon carbide by FB-HAJM

This proposed study represents the development of hot abrasive jet machine setup as well as to study the parametric optimization using silicon carbide abrasive and quartz workpiece. In this research work, micromachining has been done on Quartz material by newly developed fluidized bed hot abrasive jet machine using silicon carbide abrasive particles with various grit sizes by taking different input machining constraints i.e. pressure (P), Temperature (T) and Nozzle tip distance (NTD) for analyzing the outcome responses i.e. Displacement of cut (DOC) and Material removal rate (MRR). Fabrication and modification of heating cum abrasive-air mixing chamber, abrasive delivery system and pressurized feed system are done to investigate the influence of various effects of machining process parameters. Also Grey relational analysis (GRA) has been used to find out the finest parametric combination of input machining parameters.

Study of Micro-groove Generation on Titanium Alloy (Ti6Al4V) using Novel WEDM and WECM Sequential Electro Micro Machining (SEMM) Technique

Abstract The micro-part manufacturing can be accomplished by the execution of different micro-machining techniques. The sequential machining is one of the most promising techniques which dictate the structured approach towards the fabrication of highly precise micro-features in sophisticated components. The newly coined Sequential Electro Micro Machining (SEMM) technique has been implemented for the improvement of overall machining efficiency and enhancement in surface characteristics of the part during machining. In the chain of sequential machining, the present research paper has introduced a novel sequential combination of micro Wire Electro Discharge Machining (µWEDM) and micro Wire Electro-Chemical Machining (µWECM) processes. The µWEDM process was carried out on the standard wire cut EDM machine, whereas µWECM was performed on indigenously designed and developed system setup. The micro-grooves on difficult to cut material such as titanium alloy (Ti6Al4V) was initially generated by applying µWEDM process. The µWEDM is a thermal process, where the shaping of micro-groove was accomplished rapidly due to the existence of high-intensity spark discharges. The spark produced also generates recast layer comprising of cracks, micro-pores and numerous micro-craters in the heat affected zone of the machined region. During experimentation, the micro-groove using µWEDM process was cut at different machining voltages. In order to make out the best sequential machining combination, the machining voltage at which the least surface defects occurred on micro-groove was selected for sequencing with the subsequent process. In present experimentation, the least width overcut of the groove was obtained at 10V. The µWECM process was then applied to ameliorate the surface defects and other irregularities imparted to micro-groove during the µWEDM process. The effects of machining process parameters in µWECM, such as applied voltage, machining time and duty ratio on µWEDMed part was investigated. The sequential machining experiments were then conducted by choosing the best input process parameters in both the processes. The experimental results thus obtained after the application of diversified sequential micro-machining processes revealed an improved machining efficiency and high surface quality of micro-groove. Thus the µWEDM process for shaping the groove and µWECM process for finishing the groove was conducted successfully

Grey Relational Analysis for Wire-EDMed HCHCr using Taguchi's Technique

In this study, effect of machining process parameters viz pulse-on time, pulse-off time, current and servo-voltage for machining High Carbon High Chromium Steel (HCHCr) using copper electrode in wire EDM was investigated. High Carbon High Chromium steels have low machinability comparing to other steels and so wire EDM machin-ability was investigated in this work. Experiments were conducted according to Taguchi's technique by varying the machining process parameters at three levels. This statistical technique helps in reducing cost and time by limiting the number of experiments. Interested output parameters are Material Removal Rate, Surface Roughness and Vickers Hardness. Grey Relational Analysis was performed to find out optimized set of input parameters for achieving better output responses. It was observed that parameters of experiment 1 are highly influencing for obtaining optimized output responses.

Multiple-response optimization for surface quality and productivity during turning Al 7075/SiCp composite in spray cooling environment

Effects of machining process parameters on average roughness (Ra) of machined surface and rate of material removal (M) were investigated while turning silicon carbide particulate reinforced Al 7075 (Al 7075/SiCp) metal matrix composite in air-water spray cooling environment. Quadratic models were developed for the responses. Taguchi based grey relational analysis was used to optimize Ra and M simultaneously, which revealed 206 m/min of cutting speed (V), 0.05 mm/rev of feed (f) and 0.3 mm of depth of cut (d) were the optimized parametric levels. Significance of process parameters on the multi-response quality index was verified through Analysis of Variance (ANOVA).

Study of Influence of Process Parameters in Electric Discharge Machining of Aluminum – Red Mud Metal Matrix Composite

The present paper intends an experimental investigation and mathematical modelling of electrical discharge machining (EDM) of aluminium metal matrix composites. The experiments are conducted based on the concept of central composite design of experiments to estimate the effect of machining process parameters on responses. In the present experimental investigation discharge current, open circuit voltage, pulse-on-time are treated as the input process variables and material removal rate, electrode wear rate and radial over cut are considered as the responses. Fifteen experiments with 3 replicates for each experiment are conducted on aluminium metal matrix composites. The work material which is used in the present study consists of Al7075 and 6% red mud by weight as matrix and reinforcement, respectively. During EDM, it is observed that the discharge current and pulse on-time have significant effect on machinability characteristics of Aluminium metal matrix composite (AMMC). The two factor analysis offers useful information with minimum deviation for controlling the machining parameters to improve the accuracy of the EDMed components.

EVALUATION OF OPTIMAL MACHINING PARAMETERS OF NICROFER C263 ALLOY USING RESPONSE SURFACE METHODOLOGY WHILE TURNING ON CNC LATHE MACHINE

The objective of the present work was to investigate the effects of the various machining (turning) process parameters on the machining quality and to obtain the optimal sets of process parameters so that the quality of machined parts can be optimized. The working ranges and levels of the machining process (turning) parameters are found using three factors. Cutting speed (Vc - m/min), feed rate (f – mm/rev) and depth of cut (d - mm). The Design-Expert software has been used to investigate the effects of the Machining process parameters and subsequently to predict sets of optimal parameters for optimum quality characteristics. The response surface methodology (RSM) in conjunction with second order central composite rotatable design has been used to develop the empirical models for response characteristics. Desirability functions have been used for simultaneous optimization of performance measures. Also, the ANOVA technique and utility function have been used for response optimization. Confirmation experiments are further conducted to validate the results.