Small punch tests to estimate the mechanical properties of steels for steam power plant: II. Fracture toughness

• Published in: The International journal of pressure vessels and piping 1998, Vol.75 (9), p.707-713
• Main Authors: Ha, J.S., Fleury, E.
• Format: Article
• Language: English
• Subjects: Analysing. Testing. Standards; Applied sciences; Charpy test; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fracture appearance transition temperature; Fracture energy; Fracture testing; Fracture toughness; Fractures; Installations for energy generation and conversion: thermal and electrical energy; Installations for industrial steam generation; Measurement of properties and materials state; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Nondestructive testing; Small punch test; Steam power plants; Stress analysis; Upper- and lower-shelf regime
• ISSN: 0308-0161; 1879-3541
• DOI: 10.1016/S0308-0161(98)00075-1

Accurate measurements of the fracture appearance transition temperature and fracture toughness K IC are greatly desired for engineering in steam power plant, especially from the standpoint of life extension. The current toughness of materials at critical locations is a key characteristic necessary for the remaining life analysis. For this purpose, small punch test techniques using miniature-sized specimens have been investigated on header components. Linear relationships, obtained between mechanical characteristics determined from small punch tests and from Charpy tests, have been used to estimate the fracture appearance transition temperature. Energy based and fracture stress formulations have been applied to estimate the fracture toughness in the upper- and lower-shelf regimes on a class of low alloy steels.