History
The ultrasonic technology can be found from piezoelectric effect conducted research by Pierre Curie 1880. Pierre Curie he discover asymmetrical crystals like Rochelle salt and quartz can generate electricity charge once mechanical pressure is applied. So it is obtained mechanical vibrations from applying electrical oscillations to the crystals. The frequency of Ultrasonic wave should be higher than 20,000 Hz. (Sound waves).
After of all of the research of ultrasonic technology the first ULTRA SONIC MACHINING (USM) built 1950 s. United States develop Ultrasonic machining and was used for machining materials that need tough machine.
Types
There two type of ultrasonic machining:-
• Ultrasonic Machine (USM)
• Rotary Ultrasonic Machine (RUM)
Component and equipment
The ultrasonic have 5 main different component and equipment
And all of this system depend in other:-
A- Power supply
B- Transducer
C-Tool holder
D- Tools
E- Abrasive
USM system
The ultrasonic machining use system that mainly compose concentrator, magnetostrictor, slurry and tool. magnetostrictor is create small-amplitude vibrations and revitalized at the frequency of ultrasonic
Abrasive Slurry
- The most types of abrasive
• (SiC) silicon carbide germanium, ceramics glass
• diamond (for rubies)
• (Al2O3) corundum
• (B4C) boron carbide its good in general, but also expensive
• boron silicarbide (more abrasive than B4C)
- Liquid
• Oils
• Glycerol
• Benzene
• water (the most use)
- 100 to 800 is the typical grit size
- High viscosity decreases MRR (material removal rate)
Tool holder
Tool holder connects and also holds the tool to the transducer. It practically transmits the energy and also in some situation, amplifies the amplitude of vibration. M...
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...60 HRC such as tungsten glass ,carbides and ceramics
(Rockwell Hardness (HRB or HRC) is the measuring of the hardness of materials)
Advantages
1- Drilling non circular and circular holes even in tough material
2- Its non-thermal nature so it’s less stress
3- Does not make chemical, electric or thermal effect at the surface
4- Accurate machining of brittle tough materials
5- Less disfigurement and less burr process
6- It can applied in semi-conductor materials
7- High quality finishing surface
8- Can machining any materials no matter what their conductivity.
Disadvantages
1- Low MRR (material removal rate)
2- The tool can be wears fast
3- Hard drilling deep holes.
4- Hard to obtained in Sharp corners.
5- It is not flat in the bottom of the cavity.
7- The consumption of the power is high.
8- Only can be used when the hardness of work 45 HRC or more.
- The plumb bob was used to locate the centre of the trip plate , to
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