Principles and historical background of high pressure liquid jet (HPLJ) technology is presented in the paper. This technology can be applied, among others, for production of nano particles. This target can be achieved in various type of disintegration systems developed and designed on the base of this technology. The paper describes principles of two examples of such systems: HPLJ-reactor, called also a linear comminuting system, HPLJ- centrifugal comminuting system, which prototypes have been manufactured. A linear mill, being high energy liquid jet reactor, has been developed and tested for micronization of various types of materials. The results achieved so far, and presented in the paper, show its potential for further improvement toward nano-size particle production. Flexibility of adjustment of the reactors and the mechanism of the process allows for the creation of particles with unprecedented rheology. The reactor can be especially suitable to micronize, mix and densify materials with a wide range of mechanical properties for various industrial needs. Presented prototypes of comminution systems generate interesting potentials toward production of nano particles. Their performance, based on up today research, confirms expected high efficiency of materials disintegration, which opens a new challenge for industrial applications. The paper points out benefits and area of possible applications of presented technology.

On the base of experience in development of Magnetic Powder Composites, and particularly Soft Magnetic Composites, authors are trying to systematize classification and indicate possible development prospective of Magnetic Nanocomposites (MN) technology and their applications in electrical converters. Clear classification and systematization, at an early stage of any materials and technology development, are essential and lead for better understanding and communication between researchers and industry involved. This concern MN as well and it seems to be the right time to make it at present stage of their development. Presented proposal of classification distinguishes various types of MN by their magnetic properties and area of possible applications. It is not a close set of types, and can be extended due to increase of knowledge concern these nanocomposites.