Hello friends, Today we will discuss about the Ultrasonic Machining, but before starting this lets see about ultrasonic wave
What is Ultrasonic wave?
This is an inaudible sound with high frequency for humans. The frequency of this wave is more than 20 kHz per second.
What is Ultrasonic machining?
1] Ultrasonic machining is the advanced machining process in which machining carry out with the help of ultrasonic wave vibration combined with abrasive slurry. This ultrasonic vibrations are between the range of 20 kHz-30 kHz.
2] Ultrasonic machining is one of the non conventional machining process which is used for the machining of hard & brittle materials like glass, carbide etc.
3] This machining uses the ultrasonic wave whose frequency is more than 20 kHz which is inaudible for humans hence this process is silent process.
Working principle of ultrasonic machining:-
1] Ultrasonic machining works on the ultrasonic vibrations of tool & abrasive slurry. The tool vibrates at high frequency more than 20 kHz & this tool impacts on the work-piece surface.
2] During this hammering action of this tool, abrasive slurry flows between the tool & work-piece surface hence this causes brittle fracture & may be chemical reaction which causes removes the material from the work-piece surface.
Ultrasonic machining diagram:-
Ultrasonic machining is consists of the following components:-
- Ultrasonic oscillator / high frequency generator
- Abrasive slurry
1) Ultrasonic Oscillator :- Ultrasonic oscillator uses the electric energy & Generates ultrasonic frequency which further sends to the transducer.
2) Transducer :- Transducer is device which converts one form of energy to another form. This Coverts receives ultrasonic frequency from Ultrasonic oscillator to mechanical vibration.
3) Horn :- The vibration amplitude produced by the transducer is not sufficient for the machining. Hence horn is used which increases the vibration amplitude. The horn also holds the tool.
4) Tool :- Tool is attached to the horn. Tool is of same shape of cavity or hole to be produce onto the work-piece surface. Tool is made of the soft material.
5) Nozzle :- Nozzle supplies the abrasive slurry to space between the tool and work-piece surface.
6) Abrasive slurry :- Abrasive slurry is mixture of the water and the abrasives. The abrasives used are boron carbide, silicon carbide etc.
Working of ultrasonic machining:-
1) When power supply gets on, ultrasonic oscillator starts sending the ultrasonic frequency to the transducer.
2) The ultrasonic oscillator takes this ultrasonic frequency from the ultrasonic oscillator and starts producing the vibration.
3) When the transducer starts vibrating, the horn and tool also starts vibrating. The horn increases the amplitude of this vibration from transducer.
4) Due to this ultrasonic vibration, the tool starts impacting on the tool & abrasive slurry from nozzle starts flows between the tool & work-piece surface.
5) Hence due this hammering action on the abrasive slurry causes the brittle fracture & may be chemical reaction or corrosion which causes removes the material from the work-piece surface.
So in such way ultrasonic machining works.
Advantages of ultrasonic machining:-
- High machining accuracy.
- It can be drill different shapes hole.
- The ultrasonic machine can be handle by the semi-skilled operator.
- It can be used for the conducting & semi-conducting material work-piece.
Disadvantages of ultrasonic machining:-
- It cant machined large surfaces since it is limited for small size surfaces.
- Less material removal rate (MRR).
- Tool has shorter life due to the ultrasonic wave vibration.
Application of the ultrasonic machining:-
- In machining of the brittle materials such as glass, carbide.
- For drilling holes of any shapes.
- For the making slots onto hard material.
- In step drilling of the wok-piece.