Abstract: A method for the thermochemical surface treatment of workpieces in a reactive gas plasma is disclosed in which an appreciable reduction in the amount of reactive gas and energy used is achieved by working at gas pressures below 10 pascals (Pa). Particularly advantageous results are achieved with a low-voltage electrical arc discharge, which leads to an ionization of the gases used (about 50%) that is substantially higher than that, which is achieved with the methods described in the art 6 (approximately 1%). Surfaces, treated by such a conduct of the reaction, are distinguished by an increased hardness and better wear properties. The method of the invention moreover allows more numerous variation possibilities than do the methods described in the art and enables the conduct of the method to be adapted in a flexible manner to the specific requirements of the particular case.

Abstract: In the previously used methods for the deposition of layers on surfaces by means of chemical reactions with gases, which are introduced into the reaction room or chamber (chemical vapor deposition, CVD), electrical glow discharge and mainly high-frequency discharges were used for the activation of the reactants. According to the invention, the maintaining of a low-voltage arc discharge in the reaction room during the coating is recommended. The surprising result of this is a considerably stronger activation and ionization and a more uniform coating also on surfaces of complex shape.