Creep behavior of a new cast austenitic alloy (original) (raw)

A new cast austenitic alloy, CF8C-Plus, has been developed by Oak Ridge National Laboratory (ORNL) and Caterpillar for a wide range of high temperature applications including diesel exhaust components and turbine casings. The creep strength of CF8C-Plus is over ten times greater than that of the standard cast CF8C stainless steel and comparable to the highest strength wrought commercial austenitic stainless steels and alloys, such as NF709. The creep properties of CF8C-Plus will be discussed in terms of alloy design methodology and the evaluation of long-term creep tested specimens (over 20,000 hours). Microcharacterization shows that the excellent creep strength is due to the precipitation of very fine nanoscale and stable MC carbides without the formation of deleterious intermetallic phases.