UNS S31035 austenitic stainless steel grade is a newly developed advanced heat resistant material for use in coal fired boilers at material temperatures up to 700°C. This new grade that has recently obtained two AMSE code cases shows good resistance to steam oxidation and flue gas corrosion and higher creep rupture strength than other austenitic stainless steels available today. This paper will mainly focus on the characterization of long term structure stability and performances such as the creep behaviors at different temperatures for up to 86 000 hours and low cycle fatigue behaviors at high temperatures. The creep and fatigue damage mechanisms were studied using electron transmission microscopy and electron channeling contrast image analysis. The testing results were discussed combining with the safety and structure reliability of the material in 700°C power plants. The material is an excellent alternative for superheaters and reheaters in future high-efficient coal fired boilers.
Paper published with permission.