Micro machining Research Papers - Academia.edu (original) (raw)

The applications of advanced engineering materials such as glass, quartz, ceramics, and composites are escalating in the field of Micro-electro Mechanical system owing to their wide scope of utilization in product miniaturization. Electro-Chemical Discharge Machining (ECDM) is a proven technology for machining these materials with micro-features by combining the machining features of Electro-Discharge Machining (EDM) and Electro-chemical Machining (ECM) processes simultaneously. This machining process has drawn significant interests as it enacts a platform for new opportunities and applications owing to the potential of machining materials in a more efficacious and productive way. In this present paper, an overview of the ECDM process and influence of the process parameters such as Electrolyte parameters, Electrical parameters, Tool electrode parameters, etc. have been carried out on the response parameters such as Material Removal Rate (MRR), Surface Finish and Tool Wear. The experimental study has been performed to evaluate the influence of process parameters on MRR using one factor at a time (OFAT) approach. Results revealed that MRR increases with the increase in applied voltage and electrolyte concentration due to an increase in the spark intensity. It has been concluded that process parameters have a significant impact on the efficacy of the machining process and selection of its optimum range is very crucial for attaining high-quality characteristics especially during machining repeatability. Moreover, areas of future research in electrochemical discharge machining are highlighted.

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- Advanced Manufacturing, Non-conventional manufacturing, Micro machining

Abrasive jet machining (AJM) is a manufacturing technology based on erosion localization and intensification. AJM has a progressively important influence on the machining technology market. Over the past 20 years, there has been an exponential growth in the number of papers that discuss AJM. Various innovations and process developments such as intermittent, submerged, thermally assisted and other jet conditions were proposed. This paper examines AJM’s technological advantages and the variety of machining operations in different industries where AJM is utilized. Particular attention is devoted to the micro-texturing capabilities of powder blasting and its application in tribology. New evidence of ductile and brittle material removal mechanisms are reviewed together with recently discovered elastic removal mode. The effects of hydraulic, abrasive and machining parameters on particles kinetic energy, machined surface roughness and footprint size are described in detail. Nozzle wear has a strong dependence on nozzle materials, its geometry, particles size, hardness, and flow rate. The trend of AJM development is a shift from macro to micro scale. Improvements in micro-machining resolution, process controlling and erosion prediction are current challenges facing AJM.

Abrasive waterjet machining (AWJM) is a new machining process, the advantages of which include low cutting temperatures, no heat damage to the material being cut, minimal dust, and low cutting forces. This paper presents a state of the art review of research in this new process. The main topics discussed are mechanics of material removal, productivity, cutting forces, surface quality and nozzle wear.

A R T I C L E I N F O Keywords: abrasive jet machining micro-machining surface texturing solid particle erosion artificial joints A B S T R A C T Hectares of tribological micro-texture must be machined per year to reduce friction and wear in artificial ar-ticular joints. Productive and cost-effective tribo-texturing of freeform surfaces consisting of hard-to-machine materials is a current manufacturing challenge. This study evaluates the accuracy and productivity of micro abrasive jet machining when fabricating micro-channels on metal in a mask-less way. The influence of micro abrasive jet process parameters on micro-channel's geometry and fabrication speed is in focus in this study. We blast 27-μm alumina powder through Ø0.5 mm nozzle at Co-Cr-Mo substrate under 0.1-0.8 MPa of air pressure, 30°-90°of nozzle angles and 0.5-3.5 mm of stand-off distance. Measurements show that the micro-channels can be as narrow as 110% of the nozzle diameter and have V-, U-or W-shaped bottom at the particular stand-off distance and air pressure. The fabrication speed of 550 μm × 5 μm channels (width × depth) reaches 260 mm/ min and allows to texture the femoral head of a hip joint within several minutes using a single nozzle and a few grams of abrasives. Overall, the accuracy, productivity and cost-effectiveness of micro abrasive jet machining are highly suitable for tribological surface texturing of artificial joints.

- by Ruslan Melentiev
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- Surface Texturing, Tribology, Surface Roughness, Micro machining
- by Kaleem Sami
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- Micro machining

Wire electric discharge grinding has been developed
to generate cylindrical profiles on hard-to-machine
microparts. The outcome of the part is influenced by the
process conditions and the rotational speed of the spindle.
This paper investigates the effects of machining parameters
on material removal rate (MRR), surface roughness and
circularity during wire electrical discharge grinding process
of tungsten carbide workpiece. Experiments have been carried
out by varying process conditions such as peak current,
open circuit voltage, pulse off time, servo voltage and number
of passes. Pulse current has the highest significance to
obtain maximum MRR. To obtain the best surface quality,
pulse current, number of passes and pulse off time are identified
as the most significant parameters. Using the technique
of order preference by similarity to ideal solution, the
optimal conditions estimated are pulse current (38 A), open
circuit voltage (60 V) and pulse off time (24 μs) for finish
machining.

- by Parthi PSG and +1
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- Micro machining

This paper presents the modeling and simulation of deformation of thin-wall section using finite element method
(FEM). A 3D non-linear numerical model was developed by employing Johnson-Cook material constitutive
model for aluminum 7075-T6 alloy. Johnson-cook damage law was adopted to account for damage initiation
and chip formation during cutting tool penetration into the work material. The deformation of thin-walled part
under the action of cutting forces during milling operation was studied for a set of process conditions and the
preliminary results are discussed.

- by BEST Journals
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- Engineering, Micro machining, Electrochemical Machining

Abrasive Water Jet Machining (AWJM) is one of the most popular unconventional machining processes used to machine difficult-to-machine materials. Apart from regular cutting, it is also used for turning, threading, slotting, milling, etc. This paper details the experimental investigations on Abrasive Water Jet Pocket Milling (AWJPM) on Titanium (Ti6Al4V) using garnet abrasive. The influence of waterjet pressure, step-over, traverse rate and abrasive mass flow rate were studied on the output responses such as depth of cut and surface roughness (Ra). The experiments were designed using L9 Orthogonal Array and ANOVA analysis helped in determination of significant process. ANOVA analysis on depth of cut indicated that step-over and traverse rate are the most significant process parameters. However, ANOVA analysis for surface roughness (Ra) was inconclusive and the significant process parameters could not be determined.

- by Radhik Rammohan
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- Precision manufacturing, Micro machining

A laser micro machining is becoming popular in the industrial world due to its unique characteristics. Miniaturization has changed the path of machining of various materials. The various properties such as high peak intensity, precision, non-thermal interaction and flexibility make micro-laser machining a well accepted tool of machining. The major advantage of laser micro machining is lower aspect ratio, precise laser cutting zone, flexibility and fast processing. The objective of this review article is to analyze the various laser micromachining techniques, challenges in application, research carried out and their characteristics. This article also depicts the comparison between different laser micro-machining sources which have direct impact on the quality of machined surfaces. A comparison between pico-second, micro-second and nano-second laser has been explained with respect to fluence ablation in the machining zone.

- by ROSHAN RAMAN
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- Lasers, Micro machining

In this study, directional friction effects by creating asymmetrically shaped dimpled surfaces on an aluminum workpiece were investigated. The surfaces were created using the inclined micro-flat end milling process. Inclined micro-milling forces were modeled, and subsequent comparisons with the measured forces have provided validation. These simulations also showed that the flat end mill used to produce these dimpled surfaces was not symmetric. Tribological characterization of the friction properties of the surface using reciprocating tribometer and a hemispherical ruby counter surface indicated that these asymmetrically shaped dimples lowered the overall friction coefficients measured under both dry and lubricated sliding conditions. Moreover, the results also demonstrated a sliding direction dependent response, in terms of the measured friction coefficients.

- by Jesus Resendiz
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- Mechanical Engineering, Tribology, Lubrication and Friction, Micro machining

In this work a Shape Memory alloy (SMA) actuated, automated Stewart platform has been designed and developed for laser based micro-machining setup. The Stewart platform are designed using SMA based actuators owing to their capability for precisely controlling displacement. The actuation studies were also performed through joule heating with linear displacement of 3 mm. The system is designed with a graphical user interface that can be integrated with the computer. The system has a capability to go have a displacement of 4 mm along the X and Y plane and 3 mm in the Z direction. The resolution is of the system is estimated to be around 0.2 mm and the accuracy will be up to 0.5 mm. The silicon wafer can be attached for the reflection of laser for micro machining. This platform is a parallel manipulator robot which converts linear motion into prismatic and two rotary axes in a planar motion. Design of Stewart platform equipped with Shape memory alloy spring and biased springs concentrically. This setup will be used for generating micro channels using lasers on the silicon wafer.

- by Yogeshwaran Muralidharan
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- Robotics, Mechatronics, Shape Memory Alloys, Micro machining

A process geometry model determines engagement angle and instantaneous uncut chip thickness which forms basis in predicting cutting forces and surface quality in micro-end milling operation. This paper presents a process geometry model incorporating cutter runout, elastic recovery of work material and minimum chip thickness. These characteristics are incorporated effectively by realizing different engagement cases that are likely to occur during micro-milling. The model considers interactions of tooth trajectory under consideration with surfaces generated by previous teeth to develop a realistic process geometry model. It has been demonstrated that the inclusion of tooth trajectory interactions has significant effect on prediction accuracy of a model. The results are also substantiated by conducting machining experiments at various cutting conditions.

- by Tesfaye M Moges
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- Manufacturing, Machining, Micro machining, Milling
- by Rajes Ram
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- Precision manufacturing, Micro machining

Deviation in machining process due to the temperature influence, cutting force, tool wear leads to highly inferior quality of finished product, especially in high speed machining operations where product quality and physical dimensions seems to be meticulous. Moreover, temperature is a significant noise parameter which directly affects the cutting tool and work piece. Hence the aim of this project work is to study the machining effect on 6063 Aluminium alloy at varies combinations of process parameters such as speed, feed rate and depth of cut; and also to determine the effect of those parameters over the quality of finished product. A L 27 Orthogonal Array (OA) based Design of Experiments (DOE) approach and Response Surface Methodology (RSM) was used to analyse the machining effect on work material in this study. Using the practical data obtained, a mathematical model was developed to predict the temperature influence and surface quality of finished product. The ultimate goal of the study is to optimize the machining parameters for temperature minimization in machining zone and improvement in surface finish.

- by KANNAN A
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- Non Traditional Machining, Machining, Micro machining