Abstract
In order to reduce CO_2 emissions for environmental protection and to conserve energy, improved efficiency has been sought in power plant design through higher temperature and pressure. In the later half of the last century great progress in material development for power applications was seen to improve thermal efficiency with increasing steam temperature. For further improvement in the thermal efficiency of fossil-fired power plants with ultra supercritical steam parameter conditions aiming at temperatures above 700℃, material development concepts and material issues with increasing seam temperature will be reviewed and discussed in this paper.
