THE DIFFUSION-CONTROLLED THERMAL AGEING PROCESSES IN CONSTRUCTIONAL STEEL 15Х2НМФА

Abstract

During the exploitation at nuclear power plants the metal details are exposed at the temperatures in the range of 290 – 320 °С. It can leads to development of thermal ageing processes and to decreasing the embrittlement resistance. The steel properties degradation is taking into account by introduction the value of critical embrittlement temperature shift. The thermal aging processes are controlled by diffusion of carbon and associated with separation of the carbide phase. The presented data secure the prognosis of steels properties and critical embrittlement temperature shift for 60 years resource.