Three groups of electrode materials for CRAPED were considered: dispersive-hardening ceramic materials with effect of simultaneous strengthening of carbide grains and metallic binder result in precipitations which appeared due to concentration separation of supersaturated solid solutions; nanoparticles disperse-strengthened composite materials based on titanium carbide and diboride with modified structure produced using focused alloying by refractory compounds nanoparticles which are modificators affected to the process of structure formation thought the liquid phase and lock the recrystallization; nanocomposite cemented carbide. Mechanisms of concentration separation of supersaturated solid solutions are discussed. The follow requirements to electrodes are proposed: high volume of grain boundaries; average grain size of refractory compound phases could be around 0.1 µm and less; precipitated or/and involved nanosized particles are distributed homogenously on the grain boundaries around refractory phases; refractory compound phases of electrode material could be wetted by the melt of substrate metal.

Coatings deposited using those three groups of electrodes materials has a raised hardness, elastic recovery, adhesion strength to substrate, heat resistance, and reduced friction coefficient. Simulations of the polarity mass-transfer coefficient in spark of discharge for micro- and nanostructured electrode materials was carried out using Palatnik’s criteria. Coatings thickness more than 50 µm at high density and lower roughness were achieved due to high erosion energy of anode at high frequency and respectively lower pulse discharge energy. Coatings phase and structure formation on Ti-, Ni-, Fe- substrates are discussed. Examples of successful industrial application of CRAPED technologies are demonstrated.

TiN/AlN superlattice has a significant property that its film hardness increases depending on its bilayer period. At the bilayer period of 2.5nm the maximum hardness was obtained and AlN layer formed in a metastable cubic structure phase that is stable under high pressure environment. Because TiN/AlN superlattice has high hardness and high oxidation resistance, it is successfully used as a protective coating for cutting tools.

TiN/AlN nanomultilayer films with different bilayer periods and thickness ratios of TiN to AlN each layer was prepared onto cemented carbide substrates by using cathodic arc evaporation. Both Ti and Al metal targets were evaporated simultaneously in nitrogen atmosphere. The thickness ratio of TiN to AlN was changed by each arc discharge currents, and bilayer period was controlled by varying the rotation speed of substrate holder on the rotation table. Film hardness was evaluated with micro Knoop hardness measurement. Film hardness depended on not only bilayer period but also thickness ratio. In the case of the thickness ratio TiN/AlN = 50/50 and 35/65, above 3nm, as the bilayer period decreased, its hardness decreased. At the bilayer period about 2.5nm, the film hardness drastically increased, and then it decreased again under 2.5nm. However, in the case of the ratio TiN/AlN=25/75 and 20/80, AlN layer was thicker, film hardness simply decreased as the bilayer period decreased. Hardness enhanced effect was not appeared.