Method of producing heat-resistant high chromium ferritic/martensitic steel

摘要

Disclosed is a method of producing heat-resistant high chromium ferritic/martensitic steel, in detail, a method of producing the heat-resistant high chromium ferritic/martensitic steel, which includes melting, hot working, and heat treatment processes. In this regard, the heat treatment process includes a normalizing step at 1030 - 1100 DEG C (first process), a first tempering step at 620 - 720 DEG C (second process), and a second tempering step at 730 - 780 DEG C (third process). In the heat-resistant high chromium ferritic/martensitic steel, chromium carbonitride with a size of tens of nanometers is distributed to greatly stabilize the structure of the martensite lath, thereby enabling the heat-resistant high chromium ferritic/martensitic steel to have superior impact properties and creep rupture strength. The heat-resistant high chromium ferritic/martensitic steel is usefully applied to nuclear fuel claddings, heat transfer tubes, and pipes of nuclear power plants, and pipes, tubes, turbines and the like for the boilers of fossil power plants, which must have superior creep rupture strength and impact properties at a high temperature of about 600 DEG C. <IMAGE>