Characteristics of Plasma Flame in Metal-Cutting Apparatus of the Transferred-Type Plasma-Jet System

Studies were made of the characteristics of the plasma flame in trial-manufactured 60-to l00-kW metal-cutting apparatus of the transferred-type nitrogen plasma-jet system. First, the enthalpy of the plasma flame was measured, and the mean temperature was sought. Next, the line spectra radiated from singly ionized ions of nitrogen were utilized to measure the temperatures of the plasma flame. The maximum temperature was about 30 000°K. The speed of flow of the plasma flame was also sought using a high-speed streak camera. The maximum speed was approximately 5000 m/s.