Low cycle fatigue strength of butt-welded steel joint by means of new testing system with image technique

In this study, we investigated the low cycle fatigue strength of welded joints using a new fatigue testing system in which the image analysis technique was used to measure the strains in specimens. After checking the validity of the testing system, we used this new system to conduct fatigue tests on welded joint specimens. The test results indicate that the fatigue strength of welded material (weld deposit and heat affected zone) is much lower than that of the plain material.