Issue 30

P. Corigliano et alii, Frattura ed Integrità Strutturale, 30 (2014) 304-310; DOI: 10.3221/IGF-ESIS.30.37 304 Focussed on: Fracture and Structural Integrity related Issues FE analysis of cruciform welded joints considering different mechanical properties for base material, heat affected zone and weld metal Pasqualino Corigliano, Vincenzo Crupi, Eugenio Guglielmino Department of Electronic Engineering, Chemistry and Industrial Engineering, University of Messina, Contrada di Dio - 98166 - Sant'Agata, Messina, Italy pcorigliano@unime.it , crupi.vincenzo@unime.it, eguglie@unime.it Wolfgang Fricke Hamburg University of Technology. Institut für Konstruktion und Festigkeit von Schiffen w.fricke@tu-harburg.de A BSTRACT . The aim of this scientific work was to investigate the behaviour of cruciform welded joints under static loading using a full-field technique: Digital Image Correlation. The material curves, relative to different zones (base material, heat affected zone, weld), were obtained by hardness measurements, which were done by means of a fully automated hardness scanner with high resolution. This innovative technique, based on the UCI method, allowed to identify the different zones and to assess their different mechanical properties, which were considered in the finite element model. Finally the finite element model was validated experimentally, comparing the results with the measurements obtained using the Digital Image Correlation technique. K EYWORDS . Cruciform welded joints; Ship structures; Hardness measurements; Digital Image Correlation; FE analysis. I NTRODUCTION elds sometimes represent a weak point, due to the presence of possible crack-like defects along with high stress concentration effects and tensile residual stresses caused by the thermal welding process itself. The strength of welded structures reduces in presence of fatigue loading. The literature on fatigue analysis of welded joints was reviewed in [1, 2]. The fatigue strength of welded joints in high cycle fatigue (HCF) [4] and low cycle fatigue (LCF) [5] regimes was already investigated by the authors. The assessment of the fatigue strength becomes more complex in presence of a multiaxial stress state [6, 7] and complex structures [8]. The welding process induces variations depending also on microstructural factors. The local mechanical properties are expected to change from the melted to the heat affected zone and generally they will be different from the base material ones [3]. Local approaches are applied in these cases and are mainly based on local displacement and strain measurements by strain gauges. The aim of this scientific work was to investigate the behaviour of cruciform welded joints under static loading, considering the different material properties of base material (BM), heat affected zone (HAZ) and weld metal (WM). The material curves, relative to the different zones were obtained by hardness measurements, which were done by means of a W