Critical current densities under action of charged particles on the structural materials

The method of critical current densities allows treating the experimental values of the erosion coefficients and scattering rate in the plasma-ion technological processes. An area of charged particle interaction with a material could be represented as the area in which a direct conversion of energy from a particle to the material and the area of heat propagation into the material due to the heat conduction occur. The zone 1 can be characterized by the two external radii - maximum radius in the case of particle scattering at maximum angles and minimum radius in the case of particle scattering at minimum angles. The radii of heat influence are slightly differed by the depth. During the contact of the heat action zones of the neighboring particles the zones of their action will be merged, it is more correct to consider the action of a continuous ion flux. If the distance between the particles exceeds the double radius that means that the neighboring zones do not intersect, and the particle flow shall be examined. The distance between particles and values of the hear radii of the particle zones depend on the current density, in the particle flux and on the kind of particle. The correlation of current density in the critical situation with other particle parameters and target characteristics is also considered.