*4.7.3 Laser jet and ECM*

Electro chemical machining jet and laser drilling machining (JECM-LD) is not similar to laser drilling. It has combination of two different sources, energy of photons (laser drilling) and energy of ions (ECM), of energy simultaneously. The major purpose of combining a laser beam with a jet electrolyte is to achieve high quality machining by reducing the spatter and recast layer which is produced in simple laser drilling. As shown in **Figure 21** the focused laser beam is co-axially

**Figure 21.** *Laser cutting and EDM.*

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

aligned with a focused laser beam and tool this-electrode is not in contact with the material. The jet electrolyte and the laser beam are focused at a same time on the same location of workpiece. In JECM-LD manufacturing process, laser drilling is more responsible for material removing process and jet electrolyte effects is responsible to overcome the defects as it provides electrochemical reaction with materials, transporting debris and effective cooling to workpiece [38].

#### **4.8 Ultrasonic assisted manufacturing process-(UAM)**

**Figure 22** illustrate the fundamental approach in ultrasonic assisted manufacturing processes and most potentially effective processes are mention below.


#### *4.8.1 Ultrasonic assisted turning*

evident that the hybridization in manufacturing processes is generally driven by the

Electro chemical machining jet and laser drilling machining (JECM-LD) is not similar to laser drilling. It has combination of two different sources, energy of photons (laser drilling) and energy of ions (ECM), of energy simultaneously. The major purpose of combining a laser beam with a jet electrolyte is to achieve high quality machining by reducing the spatter and recast layer which is produced in simple laser drilling. As shown in **Figure 21** the focused laser beam is co-axially

need that emerge due to technological limitations inherent to conventional manufacturing processes. Many hybridization in manufacturing processes applied abrasion removal machining process as one of the mechanisms by which material is removed. In electrochemical grinding process the combination of the abrasive action, which continually removes the surface material layers, and electrochemical

material removal also contribute in removal of the material [37].

*Computational Optimization Techniques and Applications*

*4.7.3 Laser jet and ECM*

*EDM and mechanical machining.*

**Figure 20.**

**Figure 21.**

**110**

*Laser cutting and EDM.*

Ultrasonic-assisted turning (UAT) is a novel approach of machining operation which generate a vibration by an ultrasonic system. **Figure 23** shows basic setup for UAT and tool behavior during cutting operation. The ultrasonic system generates high frequency and low-amplitude vibrations**.** Main purpose of this method is to avoid continuous contact with the workpiece. Most desirable benefits can be

**Figure 22.** *Ultrasonic assisted process.*

#### **Figure 23.**

*Detailed view of ultra sonic turning process, 1–4 stages of the ultrasonic-assisted machining process.*

achieved such as enhanced surface quality, reduced cutting forces, and lower residual stresses in a workpiece compare to conventional turning. Ultrasonic assisted is also advantageous for the machining equipment as it allows considerable life extension of the cutting tools because of lower requirements of cutting force**.** Ultrasonic Assisted Turning, however, is more efficient at lower cutting speeds compared to conventional turning. Ultrasonic-assisted machining effects decrease by increasing speed of cutting [39–43].

pulse duration**.** The number of cycles which could run in a second control the discharge frequency**.** The pulse generator is used to control the discharge energy for a single pulse based on the requirement of machining conditions, such as finishing or semi-finishing, roughing. To maintain and to modify the spark gap and to control the movement of electrode respect to workpiece a servo control system is used. The EDM/micro-EDM system consist built in apparatus such as pump, filter, and dielectric reservoir to maintain the fresh dielectric flow in the spark gap which also

*A Review on Advanced Manufacturing Techniques and Their Applications*

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

flushing out the debris from the machined zone. **Figure 24** shows the basic sschematic diagram of ultrasonic assisted EDM/Micro-EDM system [45, 47–52].

It is observed tremendous amount of innovation and hybridization in advance manufacturing technologies. There are many researcher and universities are constantly working on innovative ideas and new technology. It can be observed that by hybridization of two manufacturing technology, more beneficial result can be achieved, and individual drawback of same process can be eliminated. Many of these innovations are potentially transformative, and not simply evolutionary. The subtractive processes and its combinations are mainly associated with the material, especially superalloys and ceramic, which are difficult to machine on the material removal processes such as milling, turning, drilling and grinding. The major contributors to material removal are EDM and other mechanical machining as such processes provided the high surface quality. Advance assisted processes such as ultrasonic vibration or laser cutting and its combination with conventional machining processes result in lower tool wear, higher surface integrity and shorter production times. Laser processing is still trending and attract many researchers to work on it in hybrid subtractive and transformative processes. It is important to be noted that the laser does not participate in actual materials removing process but introduction of it prior to the machining change the microstructures of the

**5. Conclusions**

**113**

**Figure 24.**

*Schematic diagram of ultrasonic assisted EDM.*

### *4.8.2 Ultrasonic assisted EDM*

The combination of USM and EDM has the potential to reduce tool wear and electrode deflection in EDM of micro-holes and grooves. The mechanical signal was generated and transmitted to the tool-electrode, which was applied to remove material. The tungsten carbide workpiece was being vibrated while the EDM process was carried out. To remove the burrs formed on the exit region of a drilled hole ultrasonic vibration assisted dry electrical discharge machining process is used. The result of the study proves that in lower pulse durations the performance of novel ultrasonic vibration assisted dry EDM process is better compare to dry EDM process. The positive effects of applying ultrasonic vibrations to electrode at EDM process are because of both cavitation effect of the working fluid and also the vibrational action of the electrode itself [44–46].

Electrical discharge machining (EDM) is the process which is developed to remove conductive materials in the form of small craters. Such removal of materials are ranging from several to tens of microns. Process used electric sparks between a tool, electrode, and a workpiece which is submerged in a dielectric fluid. The sparks are strictly coordinated to control material removal rate. The micro-EDM process mechanism and EDM process mechanism is fundamentally same, the only notable differences are discharge energy supplied, tool dimensions and the resolution of the axis's movement. The gap between the tool and the electrode called spark gap, the series of sparks in a controlled spark gap is responsible for material removal, a small amount of material in the form of crater were removed from the workpiece as a spark strike the material. A pulse duration [μs], series of sparks within a certain time period, which is followed by a interval [μs], define as a pause for certain time duration in the sparking process. Each discharge cycle consists of pulse interval and *A Review on Advanced Manufacturing Techniques and Their Applications DOI: http://dx.doi.org/10.5772/intechopen.97702*

#### **Figure 24.** *Schematic diagram of ultrasonic assisted EDM.*

pulse duration**.** The number of cycles which could run in a second control the discharge frequency**.** The pulse generator is used to control the discharge energy for a single pulse based on the requirement of machining conditions, such as finishing or semi-finishing, roughing. To maintain and to modify the spark gap and to control the movement of electrode respect to workpiece a servo control system is used. The EDM/micro-EDM system consist built in apparatus such as pump, filter, and dielectric reservoir to maintain the fresh dielectric flow in the spark gap which also flushing out the debris from the machined zone. **Figure 24** shows the basic sschematic diagram of ultrasonic assisted EDM/Micro-EDM system [45, 47–52].
