*4.1.1 Arc welding & mechanical machining*

In this process a 3D welding is used as an additive manufacturing process while milling process is used as a material removal process, single beads of welding is deposited side by side by using conventional gas metal arc welding. By controlling the welding parameters mainly speed and power, the thickness of bead can be set in a range between 0.5 and 1.5 mm. After deposition of a bead layer, surface of layer is machined by using milling to achieve a smooth surface with defined thickness for

**Figure 7.** *Gmaw and milling operation [2].*

#### *A Review on Advanced Manufacturing Techniques and Their Applications DOI: http://dx.doi.org/10.5772/intechopen.97702*

next weld bead deposition, as shown in **Figure 7**. The combination of this process of welding pass and with face milling offers a advantage in controlling layer thicknesses range between A0.1 and A1 mm. After the sequence of weld bead deposition and face milling is finished, surface finishing operation is take place on same machining setup in order to subtract the left stair steps pattern on the surface of the machining part and to improve the accuracy of the near-net shape metal part [2–5].

## *4.1.2 Laser cladding and mechanical machining*

The combination of selective laser cladding (SLC) and milling process result in a hybrid process and its design and construction is shown in **Figure 8**. By laser cladding a layer of material is deposited on the workpiece, and then subsequently milling operation was introduced to smooth the deposited clad surface. After the cladding operation, the engaged focal point of the laser was moved away and the workpiece was moved to the position beneath the milling head. Then, to achieve the desired accuracy and a smooth surface, the top surface of the workpiece with the deposited clad profile was machined in order to make the surface ready for the next cladding operation [6–10].
