ABSTRACT
Table 3.1 Relative economic comparisons of different machining processes (Pandey and Shan, 1980).
Machining process
Parameter influencing economy
Capital investment
Toolings/ Fixtures
Power requirements
Removal efficiency
Tool wear
Conventional machining Low Low Low Very low Low Ultrasonic machining Low Low Low High Medium Electrochemical machining Very high Medium Medium Low Very low Chemical machining Medium Low High Medium Very low Electric discharge machining Medium High Low High High Plasma arc machining Very low Low Very low Very low Very low Laser machining Medium Low Very low Very high Very low
However, lasers may have some limitations such as high capital cost, material restrictions, and some thickness limitations (Ready, 2002). Nonetheless, different types of lasers such as solid state lasers, gas lasers, semiconductor lasers, and dye lasers are used for machining with each type of laser having its own wavelength of absorption and machining applications. Table 3.2 lists the important lasers in each category. It is beyond the scope of this book to review the principles of operation of all the different types of lasers. However, a few typical lasers are discussed below.
