Fatigue strength assessment of ultra-high-strength steel fillet weld joints using 4R method

Fatigue strength of misaligned non-load-carrying cruciform joints made of ultra-high-strength steel

“…3. In addition, the reference specimens without plate misalignment were also manufactured, with the test results were initially reported in a previous study [33]. A total number of 14 specimens were fabricated and tested, with Table 3 showing the geometry and load configuration for each.…”

“…4, no welding deformations were prevented in the test specimens and, thus, low and even compressive residual stresses were measured at the weld toes despite the specimens being in the as-welded condition, similarly to reported in Refs. [33,34]. The weld geometries were measured using a 2D coordinate measuring device and the weld profile determined with a laser displacement sensor and inductive displacement transducer.…”

“…1.67 0.67 For the ENS method, the reference radius of rref = 1.0 mm was applied to assume the worst-case scenario for the transition from the base material to the weld (rtrue = 0). For the fatigue life predictions using the 4R method [33], the radius of r = rtrue + 1 mm = 0.3 mm + 1 mm = 1.3 mm, was also applied.…”

Low-Cycle Fatigue Life Prediction of 10CrNi3MoV Steel and Undermatched Welds by Damage Mechanics Approach

“…High/ultrahigh-strength steel has become an increasing choice for the manufacturing industries of machinery, marine structures, offshore structures, bridge structures, and other engineering facilities with excellent strength-to-self weight ratios and mechanical properties (Miki et al, 2002;Feng and Qian, 2018b;Ahola et al, 2019b;Chung et al, 2020). The integrity of these structures experiencing service cyclic loading under different environmental actions (e.g., wave, heavy traffic, wind, current, and seismic loadings) is directly dependent on the material fatigue properties and structural designs of local details.…”

Overview on the digitized production of welded steel structures

“…In order to utilize the increased structural performance of constructions made of high-or ultra-high-strength steels and having improved geometrical quality and compressive residual stresses (e.g., obtained by conducting highfrequency mechanical impact (HFMI) treatment), the 4R method is an efficient approach for calculating the improved fatigue strength capacity. The 4R method is applicable for welded joints and cut edges and the details can be seen in refs [26][27][28][29], and showed high accuracy particularly in the high-quality post-weld-treated details [30][31][32] failing from weld toe, as well as weld root failures [33]. The idea of the method is shown in Fig.…”