APPLICATION AND TESTING OF STEELS FOR THE ENERGY PROCESS INDUSTRY
Abstract
The aim of this paper is to analyse the fracture behaviour of high-strength low-alloyed steels for application in the energy process industry, and also to determine the relevant parameters that contribute to higher critical values of fracture toughness. For all testing of the steel specimens, fatigue pre-cracking was carried out using the GKSS Step-Wise High R ratio method (SHR) procedure. During the Crack Tip Opening Displacement (CTOD), the DC potential drop technique was used for monitoring the stable crack growth. The load line displacement (LLD) was also measured with a reference bar to minimize the effects of possible indentations of the rollers. The CTOD values were calculated in accordance with the BS 5762 standard and also directly measured via the GKSS-developed 5 clip gauge on the specimen side surfaces at a fatigue crack tip-over gauge length of 5 mm.
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References
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