Mechanical properties of VL E27 steel for shipbuilding – impact in test -50°C, 3D model of fracture

One of the basic divisions of steels used for ship hulls and ocean engineering structures is the division into: normal strength steels, high strength steels and extra high strength steels. The belonging to the group is determined by the mechanical properties of the steel, such as: yield point, ultimate strength and plastic elongation after fracture. The steels in each group are divided into categories, differing in the minimum required breaking energy at a specific temperature, determined in the Charpy test. For applications on a more responsible hull structure or offshore structure, additional steel tests may be required - determination of fracture toughness. In the shipbuilding industry, it is most often CTOD (Crack Tip Opening Displacement) test.
The published data concern testing the fracture toughness of VL E27 steel for shipbuilding, with  nominal thickness of 35 mm. It is the first steel from the group of high strength steels. It is characterized by an early low carbon content, as for hull steels, which is one of the reasons for its high ductility. The average carbon content in the tested material was 0.16%. The scope of the tests carried out so far is: tensile test at + 20 ° C, 0 ° C, -20 ° C, impact test at temperatures: 20 ° C, 0 ° C, -20 ° C, -40 ° C, - 60 ° C and a fracture toughness test at temperatures of 20 ° C, 0 ° C, -20 ° C.
Dataset contains fracture documentation - high resolution photography and 3D model (cloud of points) of fracutre. Charpy impact test temperature  -50°C.