Fracture Resistance of Welded Aluminum AlMg4.5Mn for Application in Surface Ships

摘要

In this report, the fracture resistance was determined of welded aluminumAlMg4.5Mn (5083 series) with a plate thickness of 10 mm. The results of Charpy tests at -5 deg C of the weldment show that the lowest notch toughness was measured for Charpy specimens with the notch on the fusion line. The results of quasistatic CTOD tests at -5 deg C on B x 2B 3-point bending specimens with through thickness cracks on the fusion line, ratio crack length/width a/W approx. 0.5, show a lowest CTOD of 0.06 mm. From these results, it is obvious that the weldment may have a low fracture toughness at -5 deg C. The results of dynamic CTOD tests at -5 deg C on B x 5B 3-point bending specimens with through thickness cracks on the fusion line, ratio crack length/width a/W approx. 0.3, are: The lowest CTOD is 0.13 mm, the average K (Jc) is 52 MPa square root of m, with a lowest value of 50 MPa square root of m. The results of the dynamic CTOD tests show that the fracture toughness of the weldment in AlMg4.5Mn investigated is not strain rate sensitive.