Ultrasonic treatment of the melt (UTM) of high intensity with formation of cavitation processes in the melt provides intensification of hydrogen bubble removal and thereby enhances the density of shaped castings. Generally, a short-term ultrasonic treatment allows to lower hydrogen level up to 2 and more times (example, from 0-3-0.5 to 0.15.-0.25cm³/100 g.)
Removal of hydrogen bubbles from the melt is generally transmitted with flotation of dispersed and solid nonmetallic inclusions, besides density of casting, fluidity is increasing of the melt (15-20%) and improves the filling of thin sections of the mold.
Application of the cavitation treatment of the melt in combination with the use of multi-layer glass mesh filters provides an ultrasonic degassing along with specially thin melt filtration (filter with a delay of oxide inclusions larger than 5 microns) and an additional increase in melt fluidity in combination with high-density casts and increased mechanical properties.
Ultrasonic treatment of the melt for the purpose of degassing and filtration can also be combined with a modification of the structure of casting, thereby further increase in their physical-mechanical properties. Generally ingot has a large grain structure, but if while crystallization ingot is treated by ultrasound, then ingot will have small grain structure, that will increase mechanical properties. Ultrasonic treatment of crystallizing ingot helps to grind a metal grains up to 10-20 times and lowers possibility of hot cracks appearing during casting.