Ferrous alloys cast under high pressure gas atmosphere

The main objective of this paper is describing the essence of the process of introducing nitrogen to the melt of ferrous alloys by application of overpressure above the metal bath. The problem was discussed in terms of both theory (the thermodynamic aspects of the process) and practice (the technical and technological aspects, safety of the furnace stand operation, and technique of conducting the melt). The novel technique of melting under high pressure of the gas atmosphere (up to 5 MPa) has not been used so far in the domestic industry, mainly because of the lack of proper equipment satisfyng the requirements of safe operation. Owing to cooperation undertaken with a partner from Bulgaria, a more detailed investigation of this technology has become possible and melting of selected ferrous alloys was conducted under the gas atmosphere at a pressure of about 3,5 MPa.