The article presents information on local structural nonuniformities in the tube wall metal due to which its individual zones have different susceptibility to corrosion damage processes. The presented information is based on experimental data about the structure of material (microhardness, crystallite size distribution function, and inner structural stresses of the first and second kind depending on the structural flaws density and temperature) obtained using the high-temperature X-radiography method. For a sample made of Grade 20 steel, the temperature range (350–370°C) is experimentally substantiated and determined based on the conditions of relaxing inner structural stresses of the first and second kind in which the crack surface is passivated by oxide film, which prevents the occurrence of stress concentration at the crack edge and crack propagation.
|Журнал||Thermal Engineering (English translation of Teploenergetika)|
|Состояние||Опубликовано - 1 авг 2014|
ASJC Scopus subject areas
- Energy Engineering and Power Technology
- Nuclear Energy and Engineering