Abstract: Process and apparatus for thermal cutting of workpieces, such as plate, made of materials which can be melted or decomposed thermally by means of a stream of liquid heated to a temperature above the melting or decomposition temperature of the workpiece to be cut. The stream of liquid serves to transport the heat used to melt or thermally decompose the workpiece to be cut and to induce momentum for the removal of the melted or thermally decomposed material from the workpiece. Apparatus to implement the process can comprise a crucible made of heat resistant material with an insertion opening to accept a metal wire or metal rod inserted into this opening in such a way as to be sealed. The wire is moved by feed rollers. A heating unit at the crucible melts the end of the wire or rod in the crucible. A discharge nozzle for the stream of molten metal produced.