The relatively new ferritic martensitic steel P92 (NF616) has been developed for the application in power plants. Because of its high creep resistance the material is used as pipe material, which means as thick-walled part. Within the scope of the Collaborative Research Center 561 of Aachen University of Technology P92 is planed to use as sheet metal as a component of a sandwich structure for cooling thermal high loaded parts of a steam turbine. Single segments of this cooling structure were formed by die bending into the demanded shape. Therefore it is necessary to investigate the flow behaviour as a function of temperature for this material in combination with a mathematical model. In this work quasi static tensile tests in the temperature range between 293K and 973K were performed and the results were described as a function of temperature.