Ultrasonic Machining Process

Ultrasonic Machining Process

1. ULTRASONIC MACHINING PROCESS USM .

2. . . Ultrasonic Waves of High Frequency

3. Sound . INFRA SONIC WAVES ULTRA SONIC WAVES AUDIBLE WAVES

4. SUITABLE

5. PRINCIPLE

6. .

7. . . Ultrasonic Generator Used to convert the current from low frequency to high frequency

8. Abrasive Slurry

9. . . Transducer Used to convert Electrical energy into Mechanical Vibrations

10. . . Tool Holder Made up of Titanium alloy , Monel , Aluminium , Stainless steel

11. . . Tool Material Low Carbon Material and Stainless steel The tool is brazed, soldered or Fastened mechanically to the transducer through a tool holder

12. Working of USM

13. . Transducer convert the high frequency electrical energy into Mechanical Vibrations Oscillator convert the Low frequency electrical energy into high frequency electrical energy 20 – 30 HZ Vibrations are transferred to tool material Abrasive Slurry Passed Between the vibrating tool and work piece The refrigeration system used to cool the abrasive slurry to 5 – 6 Degree celcius

14. COMPARISON

15. TRANSDUCER

16. TYPES OF TRANSDUCER

17. MAGNETOSTRICTIVE TRANSDUCER . Change in length is independent of the direction of the magnetic field But depend only on the magnitude of the field and Nature of the material

18. MAGNETOSTRICTIVE TRANSDUCER

19. MAGNETOSTRICTIVE TRANSDUCER LT battery used to heat the filament So electrons are produced Those electrons are accelerated by HT Battery So AC current Produced in the circuit

20. So Rod start to vibrate due to magnetostrictive effect This vibrations rod create Ultrasonic Waves , which sent out MAGNETOSTRICTIVE TRANSDUCER

21. MAGNETOSTRICTIVE TRANSDUCER The Longitudinal Extension and contraction of the Rod AB produce an EMF in the coil L2

22. Resonance Frequency of the oscillatory circuit Frequency of Vibrating Rod = Resonance will occur when At resonance , the rod vibrates vigorously and ultrasonic waves are produced at high frequencies

23. Advantages – Magnetostrictive Transducer

24. Disadvantages – Magnetostrictive Transducer

25. PIEZOELECTRIC TRANSDUCER Its more efficient than magnetostrictive transducer The modern USM are of this type.

26. PIEZOELECTRIC effect crystal

27. Definition - Piezoelectric Piezoelectric transducers are a type of electro acoustic transducer that convert the electrical charges produced by some forms of solid materials into energy. The word "piezoelectric" literally means electricity caused by pressure.

28. Circuit

29. Arrangement of the circuit

30. Working LT battery used to heat the filament So electrons are produced Those electrons are accelerated by HT Battery So AC current Produced in the circuit This AC current Passes through L1 and L2 and its transferred to Secondary circuit This AC current passed to the plates A and B and it make the Crystal to vibrate due to the principle of inverse piezoelectric effect. The vibrations of crystal creates Ultrasonic waves

31. Resonance

32. Advantages – Piezoelectric transducer Disadvantages – Piezoelectric transducer Piezoelectric quartz is high cost Cutting and shaping of crystal is very complex.

33. MRR MRR Per unit time

34. Wear Ratio

35. Factors considered for MRR in USM

36. Grain size of Abrasives

37. Abrasive material It Depend on 1.The type of material to be machined 2. Requirement of Surface finish For Machining - Tungsten Carbide - Die Steel Boron Carbide Silicon Carbide Abrasives For Machining - Glass - Ceramics Aluminium oxide

38. Concentration of Slurry Abrasive Slurry = Abrasive Particles + Water

39. Amplitude of Vibration MRR increase with the increase of Amplitude of Vibration

40. Frequency MRR increases with the increase of Ultrasonic wave Frequency

41. Process Parameters

42. Tool Material Lengthy tool causes overstresses So tool should be short and rigid Process Parameters

43. Process Parameters Wear Ratio 1.5 : 1 For Tungsten Carbide Work Pieces 100 : 1 For Glass Work Pieces 50 : 1 For Quartz Work Pieces 75 : 1 For Ceramics 1 : 1 For Hardened tool steel Work Pieces

44. Abrasive Material and Cutting Power Process Parameters

45. Advantages of USM

46. Disadvantages of USM

47. Applications