The Rise Of Industrial Ultrasound
The practical use of ultrasound takes its roots in 1880 after the discovery of piezoelectric effect by brothers Jacques and Pierre Curie. The effect was first discovered in rock crystal (variety of quartz).
The essence of the piezoelectric effect is the following: if the deformed quartz plate, then it faces appear opposite in sign to the electric charges, this phenomenon is called the direct piezoelectric effect. The mechanism of the direct piezoelectric effect is explained by the occurrence and the change in the dipole moment of the unit cell of the crystal lattice as a result of the displacement of the charges under the influence of mechanical stress. Thus, the faces of piezoelectric material generate electric charges.
But it turned out that there is an inverse piezoelectric effect. If applied to the plate alternating voltage, the crystal begins to shrink and expand with the frequency of the applied voltage. The mechanism of the reverse piezoelectric effect is as follows: under the action of an electric field on the charges in the elementary cell, a movement and as a result the average distance between them, that is, the deformation of the crystal occurs.
Made of a piezoelectric material part of simple geometric shapes (rod, plate, disc, cylinder, and so on) and coated with its specific surface electrodes called piezo. Piezo elements are part of a piezoelectric transducer. The inverter converts the energy of electrical oscillations in the energy of mechanical vibrations and puts it in a manufacturing environment.
Natural quartz roads is expensive, therefore created artificial piezomaterials barium titanate and lead zirconate titanate. These piezoelectric materials 100 times greater than that of quartz. Similar materials have been found among the magnetic materials and are called magnetostrictive materials. It was found that placing the magnetostrictive rod in a direction along a magnetic field alters the geometric dimensions of the rod.
On the basis of magnetostrictive and piezoelectric materials developed ultrasonic transducers transducers – devices that provide electrical energy conversion into mechanical vibrations of elastic vibrations.
But where one can use ultrasonic vibrations? One of the main applications of ultrasound is associated with the ability to transport enormous energies, aimed at the development and improvement of industrial technology. Promising direction of intensification of technological processes is the use of mechanical energy ultrasonic oscillations of high intensity.
The spheres of application
The use of ultrasonic vibration simplifies or pushes to the next level the processes that are not implemented or implemented with difficulties, traditional methods – provide machining (drilling, chamfering, performance slots) hard and brittle materials such as ceramics, semiconductor materials, glass, gems, ferrite, super-hard alloy and steel.
Ultrasonic vibrations can intensify many of the processes occurring at the interface of materials (plastics welding, gluing, impregnation of different materials), accelerating processes and improving the quality of the products. Undeniable and unique advantages of ultrasonic technology had to provide their broadest use in solving complex problems of modern industries, focused on the production of competitive products. For example, ultrasound helped to enhance the manufacturing process at large machinery facilities due to an improved cleaning and drying process. This, in its turn, gave birth to the entirely new technology – the companies like Hilsonic emerged and gave birth to numerous types of ultrasonic cleaner equipment.