Fatigue strength of welded armor steels with different weld penetration

Abstract Armor steels are crucial for their high hardness and toughness, providing protection in military and security applications, including vehicles and personal body armor. This study aims to assess the fatigue strength of welded armor steels having different weld penetration. Weld fusion or penetration (FOP) is an important issue in terms of welded joint strength. Especially in non-load carrying joints, how the fatigue strength will change with the increase in weld FOP can only be determined by the tests to be performed. In this context, the joint type was chosen as a non-load carrying cruciform joint in this study. Weld FOP is determined in terms of length in many studies. In this study, these values were evaluated in terms of unit of area as well as length. In addition to the experimental fatigue studies, specimens having different weld FOP rates were modeled and hot-spot stress analyses were performed by ANSYS workbench. As a result of the studies, a decrease in fatigue strength was determined by the increase in the weld FOP rate. The analysis revealed that as FOP rate increased, the hot-spot stress values became closer to the nominal stress.