Requirement for and Use of Coated P92 Steel for Enhanced Structural Integrity at High Temperature

To achieve climate change targets and to improve the efficiency of fossil fuel power plant the temperature and pressure of operation must be increased. With steam temperatures predicted to rise by 50100 K in the next 30 years, this presents a number of material challenges, not least for the ferritic steels used for steam pipework. Currently the best in class ferritic steel for power plant steam pipework is P92, a 912 % Cr advanced martensitic steel that was developed for its superior high temperature creep resistance. This paper will give a brief overview of P92 microstructure, composition and metallurgy and identify experimentally and computationally some key features of the material. As well as failure by creep, P92 at high temperature also suffers from steam oxidation damage. Recent literature suggests that coatings applied to P92 are a very promising solution. A short review of previous work on steam oxidation resistant coatings for P92 is included. A novel CoCrC coating that has not previously been explored for this application is described. Experimental and computational characterisation is included