Ultimate Resistance of Nickel‐free Stainless Steel T‐stubs under Static Loading

A newly developed nickel‐free, high strength austenitic stainless steel (EN 1.4678) offers excellent ductility and corrosion resistance. While its primary use is in automotive applications, its superior mechanical properties, combined with its affordability, make it an attractive material for structural applications such as structural connections which require both high strength and ductility. This paper reports, for the first time, structural tests of T‐stubs made of grade EN 1.4678 under static loading conditions. Tests on similar specimens made of conventional austenitic stainless steel EN 1.4307 and carbon steel S355 are reported for comparison. A total of 8 tests are reported, and the effects of varying the T‐stub flange material, bolt grade, and bolt spacing are investigated. All carbon steel T‐stubs failed due to fracture of the flange material, whilst for all hybrid carbon‐stainless steel T‐stubs failure was ultimately due to fracture of the bolts, due to the superior ductility of stainless steel over carbon steel. The obtained test results are compared with the design specifications for equivalent T‐stubs in tension in Eurocode 3, and cases where the specifications are inaccurate or potentially unsafe are highlighted.