This document discusses the development and generation of micro-gears using the wire electrical discharge machining (WEDM) process. The study aims to investigate the effects of various WEDM process parameters on gear micro-geometry and develop the process to achieve high production and precision. Process parameters like wire feed rate, pulse on time, and pulse off time are varied according to a Box-Behnken design of experiments. Output responses like cutting speed, material removal rate, and surface roughness are measured. Statistical analysis is performed to develop models and optimize the process.

1. M.TECH THISIS
DEVELOPMENT & GENERATION OF MICRO-GEAR BY
WIRE EDM PROCESS
Under the Supervision
of
Dr.Dipankar Bose, Professor
National Institute of Technical Teachers’ Training & Research, Kolkata.
ABSTRACT
Wire cut EDM is a high precision automatic machining process. Today, WEDM
process is the most demandable industrial machining process in the field of
gear manufacturing, preferred for its high dimensional accuracy, high
precision, high surface finish and the relative ease of adapting the process to
robotic automation. In WEDM process the machining is occurred by thermal
erosion caused by spark. WEDM machining process requires a wire electrode,
having chemical composition similar to that of the conductive material, is
continuously machining through a wire electrode.
The present study aims on investigating the effect of various WEDM process
parameters on the gear micro-geometry and develop the process performance
for achieving high production as well as high accurate and precision spur gear.
The process parameters taken under consideration are wire feed rate, pulse on
time, and pulse off time, gap voltage, group pulse, and peak current. The output
considered are cutting speed, material removal rate, and spark time to develop
the process performance and also gear micro-geometry error i.e. run out error,
pitch error, addendum error, dedendum error, root error, average surface
roughness and maximum surface roughness for studying the effect of process
parameter on gear profile. The electrode wire used in the study is of 0.25 mm
diameter of brass material. Experimental runs have been conducted on 4.57 mm
thick work pieces i.e. aluminium-6061, as per Box-behnken approach of RSM
methodology using three levels of each of the WEDM input parameters. Leica
optical microscope has been used for measuring the micro-geometry error of
gear profile at sub-micron level. Analysis of variance (ANOVA) has been done
to identify the significant process parameters which influences the output
variables and also validation of mathematical model obtained from RSM. Latin
hypercube one factor at a time approaches have been carried out to observe the
relative importance of each input parameter on the output variables
individually. RSM has been applied on the experimental data to optimize the
output variables as per maximize/minimize criteria for all the responses (i.e.
cutting speed, material removal rate, and spark time, run out error, pitch error,
addendum error, dedendum error, root error, average surface roughness, and

2. maximum surface roughness). DOE based on Box-behnken approach of RSM
methodology, optimization of the response variables and ANOVA is performed
with the help of DESIGN EXPERT, version 9 software.
For getting the optimal response value, A model independence and multi-
platform hydro particle swarm optimization have been carried out using R
environment and software.
OBJECTIVE OF INVESTIGATION
Keeping these considerations in view, the objectives of the present research
have aimed as follows:
I. To study the fundamental characteristics of wire cut electrical discharge
machining process for manufacturing of miniature spur gear as well as to
identify the problematic area of miniature gear manufacturing.
II. To study the feasibility of wire cut electrical discharge machining process for
manufacturing of miniature gear on Al-6061.
III. To carry out gear measurement technique based on gear geometry by
metallurgical optical microscope.
IV. To carry out experimental planning based on Box-Behnken approach of
RSM design methodology to perform the experiments and analyse the result for
regression modelling.
VI. To carry out analysis of variance (ANOVA) test for validation of regression
modelling.
VII. To study the relative importance of the machining parameters with respect
of each response using Latin hypercube one-factor-at-a-time approach.
VIII. To optimize the machining performance and micro-geometry error using
hydro particle swarm optimization.

3. B.TECH PROJECT
DESIGN OF A TWO STAGE REDUCTION GEAR BOX
Under the Supervision
of
Dr.Jhankar Basu, Professor
ABSTRACT
The project is to Design and Fabricate a spur gear speed reducer gear box for
Rear wheel drive differential simulation rig. This will help the motor to running
at optimal speed while output shaft will run at low required speed. This project
requires significant number of machining processes such as welding, turning,
milling, metal cutting and grinding. In this project, it needs lot of skills and
information and also knowledge such as Computer Aided Design software
(Auto Cad), Solid works software, using EDM wire cut machine, cnc milling
machine, lathe machine, band saw, bench work and welding process.