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Ultrasonic cutting is an innovative technology revolutionising the process of machining
intractable materials. In this advanced machining technique, ultrasonic vibration
(20,000 periods/second with an amplitude of 10 to 20 microns) is superimposed onto
the cutting tool's movement, transforming the process of cutting into a series of
micro-impacts. This is analogous to a micro-chiselling process as opposed to trying
to cut the material by applying a constant load to the cutter. The result of such
a transformation is impressive: the cutting force is drastically reduced (sometimes
by up to five times!) and the quality of the machined surface is superior compared
to that of conventional cutting. This allows efficient machining of high-strength
aerospace superalloys, which are extremely hard to machine using conventional methods.
Furthermore, minimum quantity lubrication or dry machining can be successfully performed
increasing the technique sustainability. This process also facilitates the cutting
of fragile materials such as glass and ceramics. It enables a mirror-like surface
to be produced, thus saving on the current costly and laborious polishing operations.
Drilling with ultrasonic assistance has proved successful even for “sandwich” materials.
It allows smooth penetration into multiple material layers and substantially reduces
burr formation, which is unavoidable when employing conventional drilling techniques.
Direct introduction of this superior technology into multiple industrial applications
was generally hindered by its instability. This is due to complicated dynamical tool–material
interaction. Recently, ultrasonic cutting technology has been optimised with the
employment of autoresonant control. This produces stable, high-amplitude vibration,
and permits its introduction into industrial manufacturing processes. Loughborough
University leads a full-scale multi-disciplinary research into ultrasonic cutting
technology. Advanced analysis methods are employed: optical, non-linear dynamical,
microstructural, and computational. The introduction of this optimised ultrasonic
technology into industry will bring manufacturing to the next level in many areas
of great importance. These include aerospace and electronics applications, and the
production of biomaterials.
Publications
1. Babitsky V, Kalashnikov A, Meadows A and Wijesundara A. Ultrasonically assisted
turning of aviation materials . Journal of Materials Processing Technology 2003;
132 (1-3): 157-167.
2. Babitsky V, Mitrofanov A and Silberschmidt V. Ultrasonically
assisted turning of aviation materials: simulations and experimental study . Ultrasonics
2004; 42 (1-9): 81-86.
3. Babitsky V, Kalashnikov A and Molodtsov F. Autoresonant
control of ultrasonically assisted cutting . Mechatronics 2004; 14: 91-114.
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