Investigation of the Effect of Ageing Temperature on a Set of Steel 15NiCuMoNb5 (WB36) Service Properties. Part I. Effect of Exposure Temperature on Steel WB36 Structural Parameters and Elemental Composition Microdistribution
摘要
In development of previous studies of steel 15NiCuMoNb5 (WB36) service properties, the results of which are presented in previous publications by the authors, this article presents results of analysis to assess the effect of thermal ageing on microdistribution of the steel elemental composition and structural parameters. It is shown that quite long thermal exposures do not affect alloying element local distribution within steel, including a welded joint transition zone. Precise microstructural studies performed by means of electron microscopy reveal an increase in secondary phase precipitation dynamics in the form of carbides and copper-containing particles from solid solution during thermal ageing.