In this paper, spectroscopic and electrostatic probe measurements are made to examine the characteristics of a supersonic dc plasma jet near the surface of titanium plate during a nitriding treatment. The low-pressure nitriding process is done using a mixture of ammonia, nitrogen, and hydrogen gasses. Heating effects from the plasma are evaluated with nickel slug and thermocouple attached to the plate. The authors present the results of their study along with observations, insights, and suggestions on how to improve plasma nitriding processes. Paper includes a German-language abstract.