Motivation. New steels supplied to the project will be subjected to state-of-the-art welding at Kværner Verdal with subsequent testing by SINTEF. The results will be important for selection of steels for more thorough examination in Tasks 2.2 and 2.3. If better HAZs and weld metals are available, the results may influence the Project Guidelines since these were made based on materials with insufficient robustness. The results will also be important for the database. It will also be seen if the philosophy of guidelines in the AM I project will be valid when other steels are tested. The weld thermal simulation is included to disclose the presence of potential local brittle zones.

Objectives.
The objectives are:

•  To examine new steels supplied in the project
• To examine welding consumables
• To revisit the instrumented Charpy V test
• To extend database for low temperature fracture toughness behaviour and provide input for model validation and definition of acceptance criteria
• To evaluate laser hybrid welding

Work description. The following sub-tasks will be included:

• Standard test programme of weldments, including tensile, Charpy and CTOD testing
• Weld thermal simulation to reveal potential local brittle zones
• Fracture toughness by individual factors as follows:
  • Effect of temperature
  • Effect of wall thickness
  • Effect of constraint
  • Effect of loading rate
• Laser hybrid welding trials and evaluation for different joint design

One PhD candidate is included here.

A large number of full sized and sub-sized fracture mechanics tests will be conducted.