Abstract
A new fatigue test apparatus with a small disk-type specimen (8 mm in diameter) was developed in the authors’ group. This testing technique was termed “Small Bulge Fatigue (SBF) test”. Unlike the small punch (SP) test, a hydraulic bulging method was adopted for avoiding problems attributable to the contact or the friction between ball and specimen. A cyclic oil pressure could be alternatively applied to both specimen surfaces at the frequency of 10 Hz. The specimen thickness of central region (gauge area) was relatively reduced to avoid cracking at the edge of specimen, and the characteristic small disk-type specimen with flat and concave surfaces was proposed considering machinability and handleability. Austenitic stainless steel SUS316 was subjected to the preliminary test using this newly developed testing technique. The obtained results indicated that this SBF test had a potential for fatigue strength assessment.
Highlights
The unplanned outage in fossil power plants is caused by various types of damage or materials degradation such as a fatigue, creep, erosion/corrosion, oxidation, wear, etc. [1,2,3,4]
Some results obtained from the preliminary tests using austenitic stainless steel SUS316 are briefly reported in this paper
The material used in this study was austenitic stainless steel SUS316
Summary
The unplanned outage in fossil power plants is caused by various types of damage or materials degradation such as a fatigue, creep, erosion/corrosion, oxidation, wear, etc. [1,2,3,4]. In the late 1970s and early 1980s, the small punch (SP) testing technique using a miniaturized disk-type specimen was developed for determining post-irradiation mechanical properties This technique has been widely used for evaluating various material properties, such as tensile property, ductile-brittle transition behavior, fracture toughness, hydrogen embrittlement, and stress corrosion cracking. It has been successfully employed in evaluating high temperature creep property This SP creep test is expected as a strong tool for assessing the heat-toheat variation of in-service USC boiler pipings, because it requires only a small amount of sample [5]. This can minimize the damage caused by removing the sample from the components. Some results obtained from the preliminary tests using austenitic stainless steel SUS316 are briefly reported in this paper
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
