*4.1.3 Shape deposition manufacturing (SDM) and mechanical machining*

One of the variations of Shape Deposition Manufacturing is a Mold SDM and various process steps can be seen in **Figure 9**. SDM is a process which include additive and subtractive manufacturing process which is used to manufacture a various metal based and polymer-based parts. Almost every layer deposition technique breaks down the model into moderately thin and uniform thickness layers. However, in the process of shape deposition manufacturing layers are 3D, also it can be of arbitrary thickness and it has not compulsion to be planar. Such a decomposition in additive process allows the quantity of layers to be limited which is leads to reduction in processing time. In Mold based Shape Deposition Method molds are constructed using SDM process, afterwards these are used to cast a various part material. For illustration, the Mold Shape Deposition Methods construct succession for a basic part with three layers**.** The shape of the mold cavity is defined by the support material segments. The mold itself is formed by the support material which are constructed around by the segments of mold material. In initial step the mold is constructed up layer by layer by Deposition Methods techniques. In later step support material is removed which allowed a mold ready for casting**.** In subsequent

**Figure 8.** *Laser cladding and mechanical machining [6].*

**4. Overview of processes (setup, procedures, manufacturing)**

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

**4.1 Additive subtractive manufacturing processes**

*Computational Optimization Techniques and Applications*

*4.1.1 Arc welding & mechanical machining*

*Sub categorization of sub hybrid manufacturing processes.*

**Figure 6.**

**Figure 7.**

**100**

*Gmaw and milling operation [2].*

**4.2 Additive and transformative manufacturing processes**

*A Review on Advanced Manufacturing Techniques and Their Applications*

ing processes. The process sequence can be seen in **Figure 11**.

**4.3 Subtractive and transformative manufacturing processes**

*4.3.1 Thermally enhanced mechanical machining*

i. Between the open halves of a mold a metal sheet is inserted.

ii. When the mold closes, the metal sheet is cut down to the defined blank size. During the same operation and on same apparatus the blank can be shaped by bending the sheet or by deep drawing metal into the basic

iii. The polymer is injected into the remaining cavity when the mold is

completely closed and a second, hydrostatic, deformation step is applied to shape the metal sheet into its definite form. In this phase of the PIF process, the physical adhesion between the metal sheet and the injected polymer is

iv. Finalizing the production cycle, the product is ready and is removed from

In the process of thermally enhanced mechanical machining externally heat sources is applied to heat the metal locally in front of the cutting tool. The heating effect changes the microstructure of the workpiece and it softened the material which allowed reduction in hardness, cutting forces and tool wear during material removing process on conventional machines. The frequently used external heat sources are laser beam and plasma. Laser assisted mechanical machining has been considered as an alternative process for machining of high-strength materials, such

as high-temperature alloys, metal matrix composites, ceramics [18–21].

Polymer Injection Forming (PIF) is a one-operation manufacturing technique and a novel approach to manufacture sheet metal/polymer macro-composite. During the process, the pressure which is exerted by the injection of the molten polymer is used to shape a metal sheet inside an injection mold. In the same step permanent bond between the metal sheet and polymer creating a fully finished product is carried out in only one manufacturing step. The Polymer Injection Forming manufacturing is a combination of the metal forming and injection mold-

*4.2.1 Injection molding and sheet metal forming*

*DOI: http://dx.doi.org/10.5772/intechopen.97702*

product shape.

obtained.

the mold.

**Figure 11.**

**103**

*Polymer Injection Forming process sequence [17].*

**Figure 9.** *SDM and machining.*

stage after part material cured it removed from the mold and finishing operation take place, for example removal of gates and runners. An alternative method also can be applicable in which the mold material is used as a fixturing during finishing operations and then it can be remove in later stage [11–14].

### *4.1.4 Injection molding and machining*

Klelkar et al. developed a re-configurable molding process by using movable pins, as shown in **Figure 10**, to generate a cavity in the mold, the process has limitation as a part surface is only approximated. According to the change of product design the pins can be re-positioned, and a required mold cavity can be produced. Kelkar and Koc introduced multiaxis machining in re-configurable mold tooling. Multi-axis machining was used to improve the surface accuracy of the part after a part is molded. The both process was carried on same setup and make it suitable for a batch production [15, 16].

**Figure 10.** *Injectioun molding and machining.*
