Paper Title
A Comparative Study Of Process Parameters In The Selection Of Non-Traditional Machining (NTM) Processes For Optimization

Abstract
The modern machining methods also known as Non-Traditional Machining (NTM) processes utilize sources of energies like mechanical, thermal, electrical, and chemical energies for material removal from the work piece without any physical contact between the tool and the work piece. This is in contrast to the conventional machining processes wherein there is a physical contact between the tool and the work piece material and employ electric motors and hard tool materials. The development of advanced machining processes where the physical properties of the work piece material do not impose any restriction on the material removal procedure can generate complex geometrical shapes in harder, tougher, stronger and temperature-resistant materials, such as tungsten carbides, alloy steels, high speed steels, fiber reinforced composites, ceramics and ceramic-based tools, and diamonds, as being frequently utilized in aerospace, electronics, nuclear, missile and automotive industries. NTM processes are capable of generating complex shape geometries, such as internal and external profiles, or small diameter holes with better surface finish, close dimensional tolerance, high accuracy, greater surface integrity and required miniaturization. Moreover, in some cases, the work pieces are too flexible or slender to withstand the cutting or grinding forces generated during the conventional machining processes But the NTM processes have relatively high capital investment cost, power consumption and operating cost, tooling and fixture cost, and maintenance cost which can easily offset the benefits elicited from the enhanced machining capabilities of those processes. A NTM setup is usually complex, which demands skilled personnel for its proper operation and maintenance.There are as many as 20 NTM processes or more. The efficiency of a NTM process is considerably affected by any change in the type of application and required attributes of the end product. The process engineers in an NTM industry have the responsibility of suggesting and identifying the most feasible NTM method. Therefore, the process engineer must have an in-depth technological knowledge regarding its applicability and characteristics. Thus, it becomes essential for a process engineer to start the selection procedure with a clear understanding of the problem, provide the required information in terms of work piece material, machining operation and finally, process characteristics, such as Material Removal Rate (MRR), and surface finish. The paper highlights in the selection of a NTM process with respect to three parameters, i.e. work piece material, machining operation and process characteristics and also on hybrid machining techniques. The aim is to help the process engineer in discarding those NTM processes which are not suitable with respect to work material limitation, machining operation description and process characteristic requirements, and gradually narrow down the list of feasible processes to arrive at the best possible decision. Keywords- NTM, USM, AJM, ECM, Laser machining.