《LM-40_Laser Beam Machining》.pdf

Module 9 Non conventional Machining Version 2 ME, IIT Kharagpur Lesson 40 Electron Beam and Laser Beam Machining Version 2 ME, IIT Kharagpur Instructional Objectives i. Describe the basic mechanism of material removal in EBM LBM ii. Identify major components of EBM LBM equipment iii. State the working principle of EBM LBM equipment iv. Draw schematically the EBM LBM equipment v. Identify the process parameters of EBM LBM vi. Identify the machining characteristics of EBM LBM vii. List three applications of EBM LBM viii. List three limitations of EBM LBM 1. Introduction Electron Beam Machining (EBM) and Laser Beam Machining (LBM) are thermal processes considering the mechanisms of material removal. However electrical energy is used to generate high-energy electrons in case of Electron Beam Machining (EBM) and high-energy coherent photons in case of Laser Beam Machining (LBM). Thus these two processes are often classified as electro-optical-thermal processes. There are different jet or beam processes, namely Abrasive Jet, Water Jet etc. These two are mechanical jet processes. There are also thermal jet or beams. A few are oxyacetylene flame, welding arc, plasma flame etc. EBM as well as LBM are such thermal beam processes. Fig. 9.6.1 shows the variation in power density vs. the characteristic dimensions of different thermal beam processes. Characteristic length is the diameter over which the beam or flame is active. In case