Abstract: A device for coating a metal or alloy layer onto an electrically conducting workpiece comprises a low pressure chamber having a workpiece support platform mounted therein. An ion producer is connected to the chamber and adapted to receive an ionized carrier gas and spender medium. An electrode of first polarity is connected to the chamber and ion producer. An electrode of opposite polarity is connected to the support platform. Arc discharge means extend into the chamber and a turbulence chamber communicates with the low pressure chamber for creating turbulence in the carrier gas.