The results of modified structure of the metal surface after the force of the directed pulsed discharge in the air are considered. The light needled formations directed within
surfaced layer of metal target are observed through a microscope in reflected light. The depth of these formations (~ 400−500 mcm) gives the position of the region with maximum hardness and maximum linear electrical resistance. The treated targets were connected with a
screen-probe (SP) on a tube with an electrodeless discharge of unipolar breakdown of gas (UBG) as a surface source of free charges and potentials of both signs.