by properly adjusting the plasma arc current as described above the sharpness of the plasma shock waves can be greatly improved sharpness of the plasma shock waves is measured in terms of the time rate of change of the plasma arc current modulating the plasma arc current without properly selecting the magnitude of the current as described above can result in a time rate of change of the plasma arc current of 10 7 amperes per second however by properly selecting the magnitude of the current as described above can result in a time rate of change of the plasma arc current of 10 8 to 10 10 amperes per second the depositing of amorphous coatings is an important use of the present invention the higher temperatures and high enthalpy of the plasma arc produced by the present invention and the multiple plasma shock waves from the plasma arc current pulses disintegrate the spray particles and their subsequent impact on the target substrate cools them faster than they are able to crystallize in order to apply amorphous spray coatings it is first necessary to set the plasma arc current according to the method described above and to modulate the plasma arc current as described above then it is necessary to adjust the standoff distance from the coating material feed of the plasma generator to the target substrate so that the deposition rate is maximum in terms of spray coating mass deposited on the target substrate per unit time the optimum standoff distance allows the spray particles enough time in the plasma to be melted and disintegrated but not too much time that they will begin to cool and.