Effect of Improvement by Applying Undermaching Weld Materials on Fatigue Strength of Load-Carrying Fillet Welded Cruciform Joints Made of High Strength Steel

Abstract

<p>Effects of the improvement by applying undermaching weld materials on the fatigue strength of the weld root of load-carrying fillet welded cruciform joints made of high strength steel were investigated through fatigue tests. Specimens were made of JIS SM570 steel plates with 17mm thick. Three types of weld material were used. 10% overmatching weld materials, 10% undermatching weld materials, and 20% undermatching weld materials were used. Test results indicate that fatigue strength of the weld roots can be improved by applying undermatching weld materials. By applying 20% undermatching weld materials, fatigue strength increased by one classes of the JSSC fatigue design recommendation.</p>