**5.3 Types of LBM techniques**

Machining using laser is generally categorized into three types namely onedimensional, two-dimensional and three-dimensional machining processes. In one dimensional machining process, the laser beam will have no relative motion with the work piece material. In this relatively stationary arrangement, the erosion front is located at the work piece and focused laser beam removes the material in the path it propagates through which is a straight line. Hence one-dimensional LBM process is generally used for drilling applications. In contrast, the work piece also will move along with laser source in two-dimensional LBM process. The erosion front placed on the beam edge and the material removal happens in a two-dimensional plane

#### **Figure 11.**

*Schematic of (a) one-dimensional (drilling), (b) two-dimensional (cutting), and (c) three-dimensional (milling) machining operations.*

resulting in a creation of two-dimensional surface as shown in **Figure 11**. Twodimensional LBM is most suitable for cutting operations. Three-dimensional LBM uses two or more sources of laser beams. Each laser beam forms two-dimensional surfaces according to their relative motion with the work piece. When the surfaces formed by each laser beams intersects a three-dimensional space is created that defines the shape of material to be removed. Three-dimensional LBM process is generally used for milling process. For better understanding of different types of LBM processes a schematic representation is given in **Figure 11** [7].
